Chlorinated hydrocarbons in the San Francisco estuarine ecosystem

Volume 19/Number

9/September

1988

~,lartne Pollution Bulletin, Volume 19, No. 9, pp. 445-453, 1988. Printed in Great Britain.

0035-326X/88 S3.oo+o.oo ~) 1988 Pergamon Press plc

Chlorinated Hydrocarbons in the San Francisco Estuarine Ecosystem D. J. H. PHILLIPS* and R. B. SPIES t *Aquatic Habitat Institute, 180 Richmond Field Station, 1301 South 46th St., Richmond, CA 94804; t Environmental Sciences Division, Lawrence Livermore National Laboratory, University of California, P.O. Box 5507, L-453 Livermore, CA 94550, USA

Data on chlorinated hydrocarbons (organochiorine pesticides and PCBs) in the San Francisco Bay and Delta, and its upstream catchment, are reviewed. Data on these contaminants in sediments and biota (mainly bivalve molluscs and teleosts) of the estuary present a consistent picture of contamination of this ecosystem. While many different organochlorines are measurable in the estuary, and some exist at elevated concentrations compared to control or more pristine areas, very little is known of their biological effects. PCBs are particularly widespread in the Bay and Delta, and it appears probable that these compounds at least are exerting detrimental impacts on some organisms. Further investigations of such effects are required if the biological resources of the estuary are to be adequately protected.

The San Francisco estuary is a large and complex system, draining a catchment of 153 000 knq 2 (about 40% of the total land area of California). The human population of the catchment is about 6 million. The margins of the Bay in particular are heavily urbanized, and many major industries discharge contaminants to the estuary. The majority of the catchment consists of the agriculturally-productive Central Valley, which drains to the estuary through the Sacramento and San Joaquin Rivers. The presence of significant industrial and agricultural development in these different portions of the estuarine catchment gives rise to contamination of the aquatic ecosystem by chlorinated hydrocarbons. This paper reviews the present state of knowledge on organochlorine pesticides and PCBs in the estuary and its upstream rivers. As is the case for most areas of the world, little information is available on the concentrations of chlorinated hydrocarbons in waters of the San Francisco estuary. This is largely a function of the difficulty of measuring such contaminants at very low concentrations. Studies to date have therefore mostly analysed sediments or biota to characterize the organochlorine levels in the system.

The various methods used to analyse and report data on chlorinated hydrocarbons create difficulties in making meaningful comparisons among studies. In most instances, concentrations of these extremely lipophilic compounds should be reported on the basis of total organic carbon in sediments and lipid content in tissues, as this provides the most useful information for interpreting chemical dynamics. However, in this review, data are reported mainly on a dry weight basis for sediments and on a wet or dry weight basis for tissues, as these are the forms in which such data have been traditionally published. Another consideration in interpreting these data is that there are at least three ways of reporting PCB concentrations. Much of the existing data is reported as Aroclor-equivalent concentrations, based on the concentrations of one to three specific peaks from PCB mixtures in the sample of interest. In some cases, isomers and congeners of a particular degree of chlorination are resolved and summed to provide a total PCB concentration. This method is used by the National Status and Trends Program of the National Oceanic and Atmospheric Administration (NOAA), in which ion-selective monitoring is used to detect trichlorobiphenyls, tetrachlorobiphenyls, etc., and these classes are then summed. Finally, individually-resolved isomers and congeners are sometimes quantified and reported.

Chlorinated Hydrocarbons in Sediments Surprisingly little information is available on the concentrations of chlorinated hydrocarbons in sediments of the San Francisco Bay and Delta. The present understanding of the spatial and temporal distribution of sediment contamination is thus very rudimentary. Law & Goerlitz (1974) analysed sieved (2 mm) surficial sediments from 26 streams which flow into the Bay (Fig. 1) at a total of 39 locations, sampled in late winter 1972. Only DDT and metabolites, PCBs, and chlordane (total) were quantified. The levels of PCBs and chlordane were estimated on the basis of comparisons of the sums of the areas of the two main sample peaks with analytical standards. The results (Table 1) revealed considerable and widespread levels of contamination by 445

Marine Pollution Bulletin

+ N

\ Pacific Ocean

0 l

50 i

i

Km

Fig. 1 Sampling locations for stream sediments in the studies of Law

and Goerlitz (1974).

e a c h t o x i c a n t a n a l y s e d . T h e s e d i m e n t s o f s e v e r a l of the s m a l l c r e e k s a n d s t r e a m s d r a i n i n g to the S o u t h B a y w e r e p a r t i c u l a r l y c o n t a n f i n a t e d , e s p e c i a l l y in t h e i r u p p e r s t r e t c h e s . I n the n o r t h e r n r e a c h o f the estuary, s e d i m e n t s f r o m U n i o n C r e e k ( d r a i n i n g to S u i s u n B a y ) a n d f r o m s e v e r a l o f t h e s t r e a m s w h i c h e n t e r the w e s t e r n s i d e o f S a n P a b l o a n d C e n t r a l B a y s w e r e also n o t a b l y contaminated. Napa River sediments exhibited a very high c o n c e n t r a t i o n o f P C B s at o n e l o c a t i o n , p r e s u m a b l y d u e to l o c a l i z e d c o n t a m i n a t i o n . A l l t o x i c a n t s a n a l y s e d were ubiquitous, and no overall gradient of contaminat i o n f r o m o n e s u b - c a t c h m e n t o f the B a y to a n o t h e r was e v i d e n t . A t s o m e sites, u n m e t a b o l i z e d i s o m e r s o f D D T w e r e f o u n d at levels s i m i l a r to t h o s e o f D D E a n d D D D , a l t h o u g h the u s e o f D D T was r e s t r i c t e d in C a l i f o r n i a in 1970, t w o y e a r s p r i o r to s a m p l i n g in this study. S e d i m e n t s o f t h e G u a d a l u p e R i v e r (at site 14 o n l y ) c o n t a i n e d 55 ng g-1 d r y wt o f p o l y c h l o r i n a t e d n a p h t h a lenes, w h i c h are r a r e l y r e p o r t e d in s u c h q u a n t i t i e s in t h e e n v i r o n m e n t ( a n d w h i c h i n t e r f e r e w i t h the analysis o f PCBs). R i s e b r o u g h et al. ( 1 9 7 8 ) c o m m e n t e d o n the p a u c i t y o f d a t a o n o r g a n o c h l o r i n e s in s e d i m e n t s o f the Bay, n o t i n g o n l y 5 d a t a p o i n t s f o r P C B s in p u b l i c a t i o n s to that time. Sites in the e a s t e r n p o r t i o n o f C e n t r a l B a y

TABLE 1

Chlorinated hydrocarbon residues (ng g-~ dry wt) found in San Francisco Bay Area streams. Sampling sites are shown in Fig. 1. After Law & Goerlitz (1974). Site 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

Stream Colma Creek Colma Creek Belmont Creek Cordilleros Creek Cordilleros Creek Redwood Creek San Francisquito Creek San Francisquito Creek Los Trancos Creek Stevens Creek Stevens Creek Los Gatos Creek Los Gatos Creek GuadalupeRiver Guadalupe River Alamitos Creek Coyote Creek Coyote Creek Alameda Creek Alameda Creek Arroyo de la Laguna Arroyo de la Laguna San Lorenzo Creek Wildcat Creek Wildcat Creek San Pablo Creek Union Creek Green Valley Creek Napa River Napa River Napa River Sonoma Creek Petaluma River Novato Creek Miller Creek San Rafael Creek Corte Madera Creek Corte Madera Creek Arroyo Corte Madera del Presidio

Chlordane

DDD

39 19 660 20 33 40 7.1 670 21 7.8 190 0.0 280 17 9.6 46 83 71 13 52 200 22 15 87 45 65 200 0.0 10 0.0 97 4.3 130 62 310 800 140 66 14(1

3.0 4.1 41 3.8 17 8.4 2.2 160 10 0.0 19 1.8 33 3.5 3.1 18 86 17 5.6 12 27 3.5 7.0 18 8.8 2.0 45 1.9 2.2 46 16 0.98 8.3 3.5 16 120 12 42 34

DDE 2.0 1.8 17 3.5 6.1 5.2 2.1 43 5.5 0.0 22 0.87 25 2.3 1.8 26 40 11 4.5 9.2 23 4.3 7.5 4.1 6.1 3.4 16 2.3 2.7 0.0 11 1.0 5.5 3.6 11 61 11 42 7.6

o,p'-DDT 1.7 0.80 89 4.0 5.2 4.2 0.96 20 1.3 0.0 11 0.28 11 0.87 0.52 2.2 5.7 2.6 0.16 2.4 4.5 0.77 0.0 2.7 1.8 2.0 2.6 0.36 0.78 9.7 2.8 0.25 3.8 2.4 13 38 8.7 6.7 11

p,p'-DDT

PCB

3.2 5.3 200 13 39 24 7.1 150 5.6 12.3 33 2.2 32 3.2 1.6 14 31 4.3 0.57 2.1 7.3 1.3 1.7 6.5 9.7 3.6 2.8 0.86 2.3 73 8.4 1.9 2.7 10 8.4 51 48 41 16

3.9 12 52 14 6.0 25 1.2 430 21 180 30 0.0 170 * 2.7 610 14 12 11 30 160 33 25 21 43 27 140 5.3 8.8 1400 7.6 5.0 27 10 35 350 81 11 24

*The presence of 55 p.g kg -~ of polychlorinated naphthalenes (PCN) obscured any PCBs present. PCN was identified by gas chromatograph/ mass spectrometer. 446

Volume 19/Number 9/September 1988

(off Oakland and Albany) showed evidence of elevated PCB levels in sediments. More recently, several studies conducted under programmes of the National Oceanic and Atmospheric Administration (NOAA) have published data on organochlorines in Bay sediments. Chapman et al. (1986) analysed sediments from three areas of the Bay (San Pablo Bay, off Oakland; and Islais Creek, on the eastern side of the San Francisco peninsula) for chlordane-related compounds, DDT and metabolites, and PCBs. The results are summarized in Table 2, and show a clear pattern of increasing contamination of sediments in the order San Pablo B a y < O a k l a n d < I s l a i s Creek. The last of these locations receives urban runoff and wet weather sewage overflows in its inner end, and is contaminated also by trace elements (Hoffman & Meighan, 1984; Chapman et al., 1986). The National Status and Trends Program of NOAA (1987) also determines chlorinated hydrocarbons in Bay sediments, and provides a comparative database for locations outside the Bay, against which local concentrations of PCBs and DDT and metabolites may be assessed. Concentrations of PCBs in sediment samples taken in 1984 at four locations in the Bay were as follows: San Pablo Bay, 9 ng g-l; Southampton Shoal, 12 ng g-l ; Oakland, 61 ng g-t; Hunter's Point, 40 ng g-~ (all values by dry wt). These are generally intermediate among locations on the west coast of the USA in terms of their degree of contamination. Sediments of relatively uncontaminated areas, such as Coos Bay or Bodega Bay, were found to contain PCBs at levels less than 10 ng g-~ dry wt; by contrast, some locations such as Elliot Bay (off Seattle in Washington State, 330 ng g-l) and San Diego Harbor (in southern California, 422 ng g-l dry wt) contained sediments which were considerably more contaminated by PCBs than those from San Francisco Bay analysed in the NOAA programme. In most cases, PCB profiles were dominated by pentachlorobiphenyls, and the overall pattern of chlorination appeared similar to that of Aroclor 1254. The concentrations of DDT and metabolites found in

sediments of San Francisco Bay by NOAA (1987) were low, ranging from less than 1 ng g-t dry wt at San Pablo Bay and Southampton Shoal to 3 to 6 ng g-t dry wt at Oakland and Hunter's Point (expressed as ZDDT, i.e. the sum of the parent compound and its metabolites). These concentrations are similar to those found at many other sites on the west coast of the USA, and are far smaller than those in contaminated locations of southern California (e.g. 28 ng g-i dry wt at Seal Beach; 621 ngg -1 at San Pedro Canyon; see NOAA, 1987). Unpublished data of the US EPA (D. J. Baumgartner, pers. comm.) have provided additional information on PCBs and DDT and metabolites in South Bay sediments, at 10 sites. PCB concentrations ranged from below detection limits to 34 ng g-t dry wt, with no obvious spatial pattern. Levels of ZDDT were less than 10 ng g-I dry wt in most locations, although sediments from one site off Coyote Point contained about 90 ng g-t ZDDT (predominantly as DDE). There was evidence of considerable spatial heterogeneity of sediment contamination. Rice et al. (in press) surveyed sediments from 18 locations in the Bay and Delta for various pesticides, PCBs, polynuclear aromatic hydrocarbons, and certain other parameters. Three of these sites, all in the vicinity of the Port of Stockton in the Delta (Mormon Channel, Mormon Slough, and the Port of Stockton turning basin) exhibited a high degree of sediment contamination, with PCB concentrations of 7100-17 800 ng g-t (dry wt, PCBs quantified as sums of Aroclors 1242, 1254, and 1260). The least contaminated sites, with PCB values of 50-90 ng g-t dry wt, were generally open, shallow, subtidal mudflats with more silty sediments, such as those found at San Pablo Bay, Berkeley, and near Richmond. The sediments of enclosed waterways along the Central Bay (India Basin, Islais Creek, Oakland Inner and Middle Harbors) and sites in Suisun Bay exhibited intermediate PCB concentrations of 100-600 ng g-~ dry wt. Differences in the ratios of the 11 individual congeners reported in this study were found to occur from place to place within the Bay.

TABLE 2 Concentrations of organochlorines (ng g-~ dry wt) in sediments from San Pablo Bay (SP), Oakland (OA), and Islais Creek (IS). After C h a p m a n etal. (1986).

Station SP02 SP05 SP09 Average Std. Dev. OA02 OA05 OA09 Average Std. Dev. IS02 IS05 IS09 Ave rage Std. Dev.

trans-Chlordane c/s-Chlordane

p,p'-DDD

p,p'-DDE

p,p'-DDT

trans-Nonachlor

Total PCB

<0.14 <0.14 d0.14

<0.11 <0.11 < 0.11

0.21 0.53 0.45

0.21 0.27 0.26

<0.10 <0.H) <0.10

<0.08 <0.08 <0.08

5.71 11.14 17.45

0.00 0.00

0.00 0.00

0.40 0.14

0.25 0.03

0.00 0.00

0.00 0.00

11.43 4.80

<0.14 <0.14 <0.14

<0.11 <0.11 <0.11

1.00 0.82 0.65

0.29 0.24 0.22

0.24 <0.10 <0.10

<0.08 <0.08 <0.08

36.84 26.57 26.95

0.00 0.00

0.00 0.00

0.82 0.14

0.25 0.03

0.08 0.11

0.00 0.00

30.12 4.75

2.02 1.08 <0.14

2.24 1.08 0.10

0.98 1.44 1.38

1.32 1.29 0.46

0.63 0.87 0.40

1.07 0.48 <0.08

179.81 255.26 57.31

1.03 0.83

I. 14 0.88

1.27 0.20

1.02 0.40

0.63 0.19

0.52 0.44

164.13 81.57

447

Marine Pollution Bulletin

These differences were not consistent with geographical area (which would indicate the likely presence of a single (or a few) predominant PCB source(s) and variations in the fate of different PCB congeners). Rather, the patterns seen suggest the presence of multiple sources of PCBs of different degrees of chlorination. It may be concluded from this limited database that the sediments of San Francisco Bay and Delta exhibit considerable spatial variability in their concentrations of chlorinated hydrocarbons. The sediments of most open areas of the estuary generally contain relatively low concentrations of DDT and metabolites (often less than 10 ng g-J dry wt), but are more contanfinated by PCBs. Site-to-site variability appears high even over short distances, however, and generalizations are difficult to completely justify. The sediments of the margins of the estuary tend to be more highly contaminated than those of open areas, particularly in regions of poor water circulation.

rington et al., 1982, 1983; Hayes et al., 1985; Martin, 1985; Hayes & Phillips, 1986; Stephenson et al., 1986) confirm the continued existence of measurable contamination of the Bay by ZDDT. California State Mussel Watch data for total DDT are summarized in Table 3. These results show no strong temporal trend in DDT concentrations over the last decade in the Bay, although data from Pacific Ocean coastal sites indicate that such a decline has occurred (Matta et al., 1986). The large persistent reservoir of DDT and metabolites which is presumably still present in Central Valley soils will probably continue to slowly release residues to the estuary for many years, maintaining this moderate 'background' level of contamination. It is also notable from Table 3 that sites in the Santa Fe Channel in Richmond Harbor are particularly heavily polluted by YDDT. This is due to the former presence of a pesticide formulation and packaging plant at this location, on the banks of the Lauritzen Canal (which drains to the Santa Fe Channel). Localized contamination by dieldrin, chlordane (dominated by cis- and trans-isomers and Chlorinated Hydrocarbons in Biota trans-nonachlor), and several other pesticides is also More data exist on chlorinated hydrocarbons in evident at this site (Hayes & Phillips, 1986; Stephenson organisms from the San Francisco estuary than are et al., 1986). The earliest data on PCBs in bivalve molluscs from available on sediments. Biota have been used in attempts to monitor local, spatial, and temporal trends the Bay are those of Girvin et al. (1975). These authors in organochlorine concentrations. In addition, research reported concentrations of 29-152 ng g-~ wet wt in has been conducted on certain key species which may four species of bivalves at three Sites in the Central and be affected by contamination. Most available data are South Bays. National Mussel Watch studies analysed for invertebrates (almost exclusively, bivalve molluscs) only one sample from South Bay for PCBs, concentraand teleosts, although a few studies of birds and seals tions found being 590 ng g-~ dry wt in 1976 and 990 ng g-~ dry wt in 1977 (Goldberg et al., 1978). Risehave also been reported. brough et al. (1978) supplemented previous studies of PCBs in mussels (Mytilus edulis) with a detailed survey In vertebrates The use of bivalve molluscs as bio-indicators of con- in 1976. These data are shown in Fig. 2. It is evident servative pollutants is now well-established (Phillips, that PCBs were ubiquitous in the Bay at that time; 1980). Local studies of this type began in the 1960s, as mussels from many locations exhibited PCB concentrapart of a national programme designed to monitor pest- tions approaching or exceeding 1000 ng g-~ dry wt. More recent data from State Mussel Watch studies, icide levels in estuaries of the USA (Butler, 1966, 1969, 1973). Much of the information relevant to San Fran- employing transplanted M. caliJbrnianus, are summarcisco Bay was summarized by Modin (1969). Pacific ized in Table 4. These results confirm the generalized oysters (Crassostrea gigas) and Asiatic clams (Corbicula contamination of the Bay, and agree well with previous fluminea) were analysed for DDT and metabolites. data from other authors cited above. There is little eviThese data suggested moderate contamination of Bay dence for any substantial temporal trend; residue levels waters, and rather higher levels of ZDDT in the Delta, reported have varied from year to year, but this may not consistent with the concept that pesticides applied to reflect true long-term temporal trends, particularly in Central Valley crops were a major source of contamina- view of the short half-lives of some PCB components in tion in the lower estuary. mussels (Tanabe et al., 1987) and the possible episodic The restrictions placed on DDT usage in California nature of PCB contamination of sampling sites by spills. in 1970 no doubt reduced the levels of this pesticide in It is certain that multiple sources of PCBs exist in the the Bay and Delta. However, subsequent studies have catchment, and no major gradient in contamination of clearly shown that DDT and its metabolites continue to the Bay appears to exist. Recent analytical improvewash down to the estuary from the upstream catchment, ments have allowed the identification of differences in presumably because of their slow release to runoff from relative peak heights of PCB components in samples soils in agricultural areas. Studies by the US EPA from different locations (Table 4, footnotes), suggesting (1974) and by Girvin et al. (1975) showed significant specific sources of Aroclors varying in their degree of concentrations of DDT and metabolites in bivalves chlorination (and probably in their precise industrial from the Bay; Girvin et al. (1975) reported ZDDT use; see Ghirelli et al., 1983; Hayes & Phillips, 1986). Data for organochlorines other than ZDDT and levels of 7-34 ng g-~ wet wt in four bivalve species at PCBs, or for invertebrates other than bivalve molluscs, three sites. More recent data from national and state 'Mussel are sparse in general. Modin (1969) reported low conWatch' programmes (see Goldberg et al., 1978; Far- centrations of dieldrin in bivalves from the Bay and 448

Volume 19/Numbcr 9/September 1988 TABLE 3

Concentrations of total D D T (DDT and all metabolites, means, ng g t dry wt) in transplanted mussels, Mytilus californianus, or native Bay mussels (M. edulis, as shown) in San Francisco Bay. Data from the State Mussel Watch Program, after Hayes e t al. (1985), Hayes & Phillips (1986) and Stephenson e t al. (1986). Location Mare Island Davis Point Point Pinole Richmond Bridge Santa Fe Ch. Mouth Santa Fe Ch. L.C. Santa Fe Ch. L.C. End Santa Fe Ch. End Richmond Inner Harbor Angel Island Fort Baker Treasure Island Alameda Yacht Harbor Oakland In. Harbor West Oakland In. Harbor Emb. Oakland Back Harbor Hunter's Point San Matco Bridge 8 San Mateo Bridge 8A Redwood Creek Mouth Rcdwood Creek Trdwnds Dumbarton Bridge 14

Station code

300.20 301.00 302.00 303.00 303.10 303.20 303.30 303.40 303.60 305.00 306.00 307.00 307.20 307.30 307.40 307.60 308.00 309.00 310.00 313.00 316.00 321.00

1979

1980

70

1981

NA NA

1982 (J/F*)

1982 (D*)

113 214

238 186 176

1983

131

1985

1986

NA ~

68

89

42

NA 10 700 2659 180

193

258 NA 265

213 101 140

122

102

357 5013 22 470 1694 264

121 136 49 165 103

216 NA NA NA 149

70 65 32 86

178

57

113 126

55

102

66

197 t 103

NA: Not analysed. *J/F/D: January/February/December, 1982. tNati~e M. edulis.

Delta, and occasional recent analyses of Corbicula flurninea from the Delta have also noted the presence of dieldrin (Linn et al., 1987). State Mussel Watch studies have expanded the range of pesticides for which samples are analysed in recent years, and data from this programme for Mytilus californianus transplanted to the Bay largely agree with studies of C. fluminea in the Delta. Minor contamination of such samples has been recorded by chlorbenside, chlordane, chlorpyrifos, dacthai, dieldrin, endosulfan, HCH isomers, heptachlor and its epoxide, hexachlorobenzene, and toxaphene. Martin et al. (1984) correlated scope for growth data for transplanted M. californianus in South Bay to their levels of dieldrin and chlordane (although no relationship was found between scope for growth and PCB concentrations in these samples). However, as noted by these authors, significant correlations also existed between scope for growth and certain trace metal concentrations, and none of these relationships can necessarily be viewed as causative in nature. Concern over the collapse of the Dungeness crab (Cancer magister) fishery in the estuary and offshore Pacific waters (Wild & Tasto, 1983) has given rise to attempts to link this with toxicants in the Bay. However, early studies of DDT and metabolites (Modin, 1969; Earnest & Benville, 1971) found high variability between individuals in residue concentrations, and could not support such a relationship between population levels and toxicant abundance. More recent studies extending to PCBs (Haughen, 1983) documented rather higher PCB concentrations in the muscle and hepatopancreas of juvenile C. magister from San Pablo Bay than in those from Humboldt Bay further north, but the toxicological significance of such differences remains unknown.

N San Pablo Bay

~)

~)

0

0 0-249 ~) 2 5 0 - 3 9 9 (D 4 0 0 - 5 4 9 • 550-699 • 700-1500

0

San Francisco

•

•

5

L Fig. 2 Concentrations of PCBs (ng g-' dry wt) in whole soft parts of native Bay mussels (Mytilus edulis) from sites in San Francisco Bay. After Risebrough e t al. (1978).

Teleosts Studies of chlorinated hydrocarbons in fish of the Central Valley catchment waters are undertaken within the framework of the Toxic Substances Monitoring Program (TSMP), which is conducted by State agencies 449

Marine Pollution Bulletin TABLE 4 Concentrations of PCBs (means, ng g-~ dry wt, as Aroclor 1254 with additional residues as noted) in transplanted mussels,Mytilus californianus, Or native Bay mussels (M. edulis, as shown) in San Francisco Bay. Data from the State Mussel Watch Program, after Hayes et al. (1985), Hayes & Phillips (1986) and Stephenson et al. (1986).

Location Mare Island Davis Point Point Pinole Richmond Bridge Santa Fe Ch. Mouth Santa Fe Ch. L.C. Santa Fe Ch. L.C. End Santa Fe Ch. End Richmond Inner Harbor Angel Island Fort Baker Treasure Island Alameda Yacht Harbor Oakland In. Harbor West Oakland In. Harbor Emb. Oakland Back Harbor Hunter's Point San Marco Bridge 8 San Marco Bridge 8A Redwood Creek Mouth Redwood Creek Trdwnds Dumbarton Bridge 14

Station code 300,20 301.00 302.00 303.00 303.10 303.20 303.30 303.40 303.60 305.00 306.00 307.00 307.20 307,30 307.40 307.60 308,00 309.00 310.00 313.00 316.00 321.00

*J/F/D: January/February/December, 1982. ~Native M. edulis. hAlso 68 ng g--~ Aroclor 1248.

1979

1980

370

690 1100

1982

1982

(J/F*)

(D*)

140 220

230 330 280

1983

1985

1986

100 a

76

78

56

180

660 b 860 c 770 790

630

830 510 1500

220

230 270 300

280

1800 1300 1200

230 180 140 200

1300

250

340 430

180

390

210

540' 500 f 970g 500 ~ 510

200

880 690 d

600 180 700 540

850 ~ CAlso 100 ngg -1 Aroclor 1248. °Also 32 ngg -l Aroclor 1260. 'Also 100 ng g-~ Aroclor 1248.

to annually survey the general abundance of a variety of toxicants in inland waters of California. The TSMP analyses freshwater fish of many species for organochlorines in axial muscle (or occasionally, in whole bodies of fish). Little attempt is made to stratify sampling by species or by size of fish. This, and the migratory or other movement of fish within the catchment, permits only broad conclusions to be drawn on areas of particular abundance of pesticides or PCBs. However, data from the last several years (see SWRCB, 1986 for review, and L i n n e t al., 1987 for the most recent results) clearly indicate the presence of elevated concentrations of many pesticides in fish of the Central Valley waters. Concentrations of DDT and metabolites, total chlordane, dieldrin, endosulfan, lindane (7-HCH), hexachlorobenzene, and toxaphene in fish muscle samples from this area have on occasion exceeded the respective guidelines for predator protection (promulgated by the National Academy of Sciences) and the Food and Drug Administration guidelines for public health. It is therefore clear that many organochlorine pesticides continue to be washed down to streams in the Central Valley, and a proportion of this toxicant load undoubtedly reaches the Delta and Bay, albeit in highly diluted form. Fish samples from the Central Valley also exhibit high concentrations of PCBs in muscle on occasion, sometimes surpassing the guideline of the National Academy of Sciences (500 ng g-i wet wt) or even that of the Food and Drug Administration (2000 ng g-~ wet wt). Particularly high contamination by PCBs near Forbestown, in fish from the Feather River (about 100 km up the Sacramento River from the Delta) was discovered in the late 1970s. Later detailed investigations of this area (SWRCB, 1981) identified a PCB spill and chronic PCB contamination from powerhouse sumps as the primary causes of this problem. 450

1981

180 fAlso 180 ngg -* Aroclor 1248. gAlso 160 ng g-a Aroclor 1248. hAlso 180 ng g-* Aroclor 1248.

Clean-up actions at that time gave rise to improvements, and PCB levels reported more recently for fish from this specific area have decreased markedly. Studies of chlorinated hydrocarbons in fish from the Delta and Bay areas have largely concentrated on a few key species of particular importance to the estuary. Early work on DDT and metabolites by Earnest & Benville (1971) documented a correlation between the lipid contents of eight species of fish from San Francisco Bay and their accumulated levels of ZDDT; this relationship has since been found in many areas and is thought to be due to the lipophilic nature of persistent pesticides such as DDT (Phillips, 1980). Most fish from the Bay contained whole-body ZDDT residue levels of 100-200 ng g-~ wet wt in the late 1960s (prior to restrictions on DDT usage in California; see Earnest & Benville, 1971). It is likely that concentrations have decreased since that time, both in the Bay and elsewhere on the west coast of the USA: however, the available database is rather poor (Matta et al., 1986). Much effort has been expended in the San Francisco estuary to attempt to identify factors contributing to the decline of stocks of striped bass (Morone saxatilis). The effects of toxicants on adults and their reproduction are possible factors contributing to this decline in striped bass abundance, although several other parameters (such as the decrease in Delta outflow) are undoubtedly also involved (e.g. see Stevens, 1979, 1980; Stevens et al., 1985). Studies of organoehlorine levels in striped bass have been relatively few, however. Stevens (1980) reported data for EDDT and PCBs in M. saxatilis from the Delta for the period 1964-1976. However, sample numbers were small in most years, and the high variability between individuals (see below) may have masked any true temporal trends in contaminant levels. More recent data suggest that ZDDT concentrations in

Volume 19/Number 9/September 1988

striped bass from the early 1980s approximated 0.5-1.0 gg g-i wet wt in axial muscle, with rather higher levels being found in livers and especially ovaries (Crosby et al., 1983, 1986; Whipple et al., 1983; Jung et al., 1984). The data of Crosby et al. (1986) for several organochlorines in M. saxatilis from the Sacramento River are shown in Fig. 3, with comparative results for striped bass from Coos River also being presented. It is clear that ZDDT, PCBs, and toxaphene are all found at higher levels in M. saxatilis from San Francisco Bay than from the less contaminated Coos River. Differences of this nature were also found by Whipple et al. (1983) for aldrin, chlordane, dacthal, dieldrin and hexachlorobenzene. Crosby et al. (1986) postulated that the PCB concentrations might be sufficient to account for reproductive problems associated with local striped bass, including the resorption of eggs. However, although female M. saxatilis are known to accumulate larger amounts of organochlorines than males (mainly because of lipid changes in female tissues prior to spawning; see Phillips, 1980), no conclusive cause-andeffect data are available on the toxic effects of these contaminants to the local striped bass population. The starry flounder, Platichthys stellatus, has also been the subject of considerable study in the estuary, especially in relation to its accumulation of PCBs. Spies & Rice (in press) reported that female P. stellatus from San Francisco Bay exhibited an inverse correlation between three measures of reproductive capacity (percentage of viable eggs, fertilization success, and embryological success) and their mixed function oxidase (MFO) enzyme activities in livers. Percentage of normal larvae did not correlate to liver MFO activities, however. The poor embryological success of P. stellams females from parts of the Bay was correlated directly to PCB concentrations in eggs (Spies et al., 1985; Spies & Rice, in press). While direct cause-and-effect relationships have not yet been conclusively proven in this case, it appears likely that PCBs, or compounds with similar chemical and pharmicokinetic properties, interfere with the reproduction of starry flounders in the Bay. Similar low concentrations of PCBs have been correlated with poor reproductive success in other fish species elsewhere (e.g. Von Westernhagen et al., 1981; Hansen et al., 1985). The variable accumulation of PCBs by starry flounder captured (and presumably, resident) in different parts of San Francisco Bay first noted by Spies et al. (1985) has recently been confirmed by the studies of NOAA (1987). PCB concentrations in livers of P. stellatus varied from 1191 ng g-i dry wt for fish from San Pablo Bay, to 3734 ng g-~ at Southampton Shoal, and to 6990 ng g-I dry wt for a sample from Hunter's Point. The last of these samples exhibited similar levels of PCBs to those found in livers of hornyhead turbot (Pleuronichthys verticalis) from the highly contaminated areas of southern California (Santa Monica Bay, San Pedro Canyon, and Seal Beach; see NOAA, 1987). By contrast, ZDDT concentrations in the samples from San Francisco Bay (1000-1300 ng g-1 dry wt) were considerably lower than those in southern California fish (3200-18 700 ng g-~ dry wt), although flounder from

'i1

Ill

ovo y

.~_

c

Q:=

PCBs

s

IjDDT

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C~

~

°

ao

t ILl

I

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4

~

o

O

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'r'D D T

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Fig. 3 Concentrations of PCBs, ZDDT and toxaphene (/ag g-~ lipid wt) in ovaries, livers and lateral line extracts of striped bass (Morone saxatilis) from the Sacramento River (S) draining to San Francisco Bay, and from the Coos River (C) in Oregon. After Crosby et al. (1986).

sites in Oregon and Washington were less contaminated than those from San Francisco. Similar relationships between sites were reported for analyses of livers of white croaker (NOAA, 1987). A recent publication by Melzian et al. (1987) also deserves brief mention here. These authors analysed Dover sole (Microstomus pacificus) and sablefish ( A n o p l o p o m a firnbria) from waters outside the Bay, in the vicinity of the Farallon Islands. Concentrations of ZDDT and PCBs in the livers of these fish were found to be similar to those reported for the same species in contaminated coastal areas of southern California (e.g. see Brown et aL, 1986). The area of sampling near the Farallon Islands contains both low-level radioactive and chemical munition disposal sites, used from 1946 to 1962. It is not known whether materials dumped at these sites, or residues derived from San Francisco Bay, are primarily responsible for this surprising level of offshore contamination of fish species. Other Species Very little information is available on chlorinated hydrocarbons in species other than bivalve molluscs and fish in the San Francisco estuary. However, a few studies on birds and seals have been reported. The Delta and the Central Valley are particularly important migratory and wintering areas for birds on the Pacific Flyway (Gilmer et al., 1982). Ohlendorf & Miller (1984) investigated the exposure of waterfowl to organochlorines during their stay in the Bay catchment, concentrating on four species (northern pintails, A n a s acuta; northern shovelers, A n a s clypeata; canvasbacks, Aythya valisineria; and lesser scaups, Aythya affinis). Analyses of birds collected early and late in the wintering period suggested the occurrence of significant uptake of DDE, PCBs, and hexachlorobenzene by these

451

Marine Pollution Bulletin species in the local area during their stay. However, in general, residue levels were deemed to be quite low, and waterfowl populations were not thought to be reduced by the toxic effects of accumulated organochlorines, either through impacts on adults or their reproduction. H o f f m a n et al. (1986) noted a possible sublethal effect of PCBs on black-crowned night herons (Nycticorax nycticorax) in South Bay, at the Bair Island National Wildlife Refuge. PCB concentrations in whole eggs correlated negatively to embryonic weights (of other eggs in the clutches sampled), and embryonic weights of this heron population were significantly lower than those of a control poulation at the Patuxent Wildlife Research Center in Maryland. In addition, crown-rump lengths and femur lengths were reduced in embryos from the local population c o m p a r e d to Patuxent embryos. No correlation of such parameters with D D E was present, and no elevation of liver microsomal aryl hydrocarbon hydroxylase existed. Various reproductive problems (congenital malformations, reduced hatching success, and low hatchling survival) have been noted in waterfowl at Bair Island (Hoffman et al., 1986), but presently available data are insufficient to link these problems conclusively to organochlorine pollution of the Bay. It is unfortunate that very little work on seal populations in the Bay has been completed. Risebrough et al. (1978) reported limited analyses of organochlorines in the tissues of harbour seals ( P h o c a vitulina) found dead in the Bay. A few individuals contained considerably elevated levels of PCBs (one adult male found dead at Richardson Bay exhibited concentrations of PCBs of 500 gg g-~ lipid weight in blubber, 12 000 gg g-i in liver, and 31 000 p.g g-J in muscle; elevated levels of D D E were also present in this individual). Work elsewhere on ringed seals (Pusa hispida) in the Bothnian Bay (Helle et al., 1976a, 1976b) and harbour seals in the Wadden Sea (Reijnders, 1980, 1986) suggests that PCB concentrations of this magnitude would be likely to cause reproductive problems in seals. However, no conclusive data are available on the reproductive success of resident seals in San Francisco Bay.

Conclusions While the database on chlorinated hydrocarbons in the San Francisco estuary is very limited, currently available information presents a consistent pattern. Thus, analyses of both sediments and biota from the estuary have revealed the presence of elevated concentrations of various organochlorines. Most notable among these are PCBs, D D E , chlordane and perhaps toxaphene; smaller amounts of many other persistent pesticides are also present. D D T and its metabolites continue to wash down to the lower estuary from upstream agricultural areas, almost two decades since restrictions on their local use were introduced. H o w ever, while it is possible to demonstrate an elevated abundance of ZDDT, chlordane, toxaphene, and many other pesticides in the estuary, these c o m p o u n d s have not been shown to exert overt detrimental effects on biota in the Bay and Delta. 452

The ubiquitous nature of PCBs in the estuary is, however, of considerable concern. Although San Francisco Bay and Delta are not as contaminated by PCBs as certain other (generally smaller) coastal areas of the USA, PCBs are widespread throughout the local estuary and show no signs of temporal reductions over the last decade. Evidence for their detrimental impacts is accumulating, and although most of the data cannot be considered conclusive at present, it appears probable that PCBs are exerting measurable damage to biological resources in the estuary. Additional studies are undoubtedly warranted if the biota of this important system are to be adequately protected in future. Such studies should concentrate on known areas of particular contamination by PCBs (and other chlorinated hydrocarbons) and on organisms of high trophic levels or particular economic or biological importance. In addition, future investigations should seek to identify real cause-and-effect relationships, as opposed to establishing correlations between parameters which may or may not be truly interdependent. We wish to thank Dr. R. J. Huggett of the Virginia Institute of Marine Science and Drs. J. N. Cross and R. Eganhouse of the Southern California Coastal Water Research Project Authority for their helpful reviews of this manuscript.

Brown, D. A., Gossett, R. W., Hershelman, G. R, Ward, C. E, Wescott, A. M. & Cross, J. N. (1986). Municipal wastewatercontamination in the Southern California Bight. Part 1. Metal and organic contaminants in sediments and organisms. Mar. Environ. Res. 18,291-310. Butler, P. A. (1966). The problem of pesticides in estuaries. In .4 Symposium opt Estuarine Fisheries. Trans. Amer. Fish. Soc. Spec. Publ. 3,

110-115. Butler, P. A. (1969). Monitoring pesticide polhition. Bioscience 19. 889-891. Butler, P. A. (1973). Organochlorine residues in estuarine molluscs, 1965-1972--National Pesticides Monitoring Program. Pestic. Monit. J. 6,238-262. Chapman, P. M., Dexter, R. N., Cross, S. E & Mitchell, D. G. (1986). A field trial of the sediment quality triad in San Francisco Bay. NOAA Tech. Mem. NOS OMA 25. National Oceanic and Atmospheric Administration, Rockville,Maryland, USA. Crosby. D. G., Hogan, K. & Bowes, G. W. (1983). The potential impact of chemical residues on the California striped bass fishery. In Third Progress Report of the Cooperative" Striped Bass Study, Appendix B.

Toxic Substances Control Program, Special Projects Report No. 833sp. State Water Resources Control Board, Sacramento. California, USA. Crosby, D. G., Hogan, K., Bowes, G. W. & Foster, G. g. (1986). The potential impact of chlorinated hydrocarbon residues on California striped bass. In Report of the Cooperatite Striped Bass Stud3: Techmcal Supplement 1, Section 1. State Water Resources Control Board, Sacramento, California, USA. Earnest, R. D. & Benville, P. E. (1971). Correlation of DDT and lipid levels for certain San Francisco Bay fish. Pestic. Monit. J. 5, 235241. Farrington, J. W., Risebrough, R. W., Parker, E L., Davis, A. C., de Lappe, B., Winters, J. K., Boatwright, D. & Frew, N. M. (1982). Hydrocarbons, polychlorinated biphcnyls, and DDE in mussels and oysters from the U.S. coast, 1976-1978--the Mussel Watch. Technical Report WHOI-82-42, Woods Hole Oceanographic Instituthm, Woods Hole, Massachusetts,USA. Farrington, J. W., Goldberg, E. D., Risebrough, R. W., Martin, .I.H. & Bowen, V. T. (1983). U.S. "'Mussel Watch" 1976-1978: an overview of the trace-metal, DDE, PCB, hydrocarbon, and artificial radionuclide data. Environ. Sci. Technol. 17,490-496. Ghirelli. R. R, Palmer, E H., Spielman, T. k., Jung, M.. Severeid, R. L., Bowes, G. W. & Cohen, D. B. (1983). Polychlorinated biphenyls. Toxic Substances Control Program, Special Projects Report No. 831sp. State Water Resources Control Board, Sacramento, California, USA.

Volume 19/Number 0/September 1988 Gilmcr, D. S., Miller, M. R., Bauer, R. D. & LeDonnc, J. R. (I982). California's Central Valley wintering waterfowl: concerns and challenges. Trans. A},rth Am. IVildl. NatL Resour Conf. 47,441-452. Girvin, D. C., Hodgson, A. "E & Panictz, M. H. (1975). Assessmem of trace metal and chlorinated hydrocarbon contamination in selected San Francisco Bay estuary shellfish. Final Report 74-51291 from the Lawrence Livermore National Laboratory to the San Francisco Bay Regional Water Quality Control Board, Oakland, California, USA. Goldberg, E. D., Bowcn, V. T., Farrington, J. W., Harvey, G., Martin, J. H., Parker, P. L., Riscbrough, R. W., Robertson. W., Schneider, E. & Gamble, E. (1978). The Mussel Watch. [~_nvilvn. Conser~ 5, 101125. Hanscn, P.-D., Ykm Westernhagen, H. & Rosenthal, H. (1985). Chlorinated hydrocarbons and hatching success in Baltic herring spring spav, ners. Mar. Environ. Res. 15, 59-76. Haughcn. C. W. (1983). Chlorinated hydrocarbon pesticides and polychlorinatcd biphenyls in Dungencss crabs. Calill Fish• & Game l:~)h. Ball. 172,239-241. Hayes, S. P. & Phillips, P. T. (1986). California State Mussel Watch: Marine Water Quality Monitoring Program, 1984-1985. Water Quality Monitoring Report No. 86-3WQ, State Water Resources Control Board, Sacramento, California, USA. I-taycs, S. P.. Phillips, P. T., Martin, M., Stephenson, M., Smith. D. & Linfield, J. (1985). California State Mussel Watch: Marine Water Quality Monitoring Program, 1083-1984. Water Quality Monitoring Report No. 85-2WQ, State Water Resources Control Board, Sacramenlo, California, USA. Helle, E., Olsson, M. & Jensen. S. (1976a). DDT and PCB levels and reproduction in ringed seal from the Bothnian Bay. Ambio 5, 188189. Helle, E., Olsson, M. & Jenscn, S. (I976b). PCB levels correlated with pathological changes in scat uteri. Ambio 5,261-263. Hoffman, D. J., Ratmer, B. A., Bunck, C. M., Ohlendorf, H. M. & Lowe, R. W. (1986). Association between PCBs and lower embryonic weight in black-crowned night herons in San Francisco Bay. J. Toxicol. Environ. Health 19,383-391. Hoffman, R. W. & Meighan, R. B. (1984). The impact of combined sewer overflows from San Francisco on the western shore of central San Francisco Bay. J. Water Pollut. Control Fed. 56, 1277-1285. Jung, M., Whipple, J. A. & Moser, L. M. (1984). Summary Report of the Cooperative Striped Bass Study (COSBS). State Water Resources Control Board, Sacramento, California, USA. Law, L. M. & Goerlitz, D. F. (1974). Selected chlorinated hydrocarbons in bottom material from streams tributary to San Francisco Bay. t'estic. Monit. J. 8, 33-36. Linn, J. D., Reiner, C., Crane, D., Smith, L. & Seto, W. (1.987). Toxic Substances Monitoring Program--1986 Data Report. Submitted by the California Department of Fish & Game to the State Water Resources Control Board, Sacramento, California, USA. Martin, M. (1985). State Mussel Watch: toxics surveillance in California. Mar. Pollut. Bull. 16,140-146. Martin. M., Ichikawa, G., Goetzl, J., de los Reyes, M. & Stephenson, M. D. (1984). Relationships between physiological stress and trace toxic substances in the Bay mussel, Mytih~s edulis, from San Francisco Bay, California. Mar. Environ. Res. 11, 91-110. Matta, M. B., Mearns, A. J. & Buchman, M. E (1986). Trends in DDT and PCBs in west coast fish and invertebrates. Report for the National Status and Trends Program, National Oceanic and Atmospheric Administration, Rockville, Maryland, USA. Melzian, B. D., Zoffman, C. & Spies, R. B. (1987). Chlorinated hydrocarbons in lower continental slope fish collected near the Farallon Islands, California• Mar. Poll,tt. Bull. 18,388-393. Modin, J. C. (1969). Chlorinated hydrocarbon pesticides in California bays and estuaries. Pestic. Monit. J. 3, 1-7. NOAA (1987)• National Status and Trends Program for Marine Enviro~mlental Quality• Progress report and preliminary assessment of findings of the benthic surveillance project--1984. National Oceanic and Atmospheric Administration, Rockville, Maryland, USA.

Ohlendorf, H. M. & Miller, M. R. (1984). Organochlorine contaminants in California waterfowl. J. Wildl. Manage. 48,867-877. Phillips, D . . I . H . (1980). Quantitative Aquatic Biological Indicators." 77teir use to monitor Trace Metal aml Organochlorine I'o!lntton. Applied Science Pu01ishers Ltd., London. Reijnders, P. J. H. (1981)). Organochlorinc and heavy rectal residues in harbor seals from the Wadden Sea and their possible effects ¢~n reproduction. Neth. .L Sea Res. 14, 30-65. Reijnders, P. J. H. (1986). Reproductive tailure in eommem seals feeding ,on fish from polluted coastal waters. Nature 324,456-487. Rice, D. W., Spies, R. B., Zoffman, C.. Prieto, M. & Severcid. R. (1988). Organic contaminants in surficial sediments of thc San Franci,~co Bay-Delta. Environ. Sci. Technol. (in press). Riscbrough, R. W., Chapman, J. W., Okazaki, R. K. & Schmidt, T. T. (1978). Toxicants in Sa~ Francisco Bay and Estuary. Report of the Association of Bay Area Governments, Berkeley, California, USA. Spies, R. B. & Rice. D. W. (1988). Effects of organic contaminants on reproduction of starry flounder Platichthvs stellatus (Pallas) in San Francisco Bay. Part 2. Reproductive success of fish captured in San Francisco Bay and spawned in the laboratory. Mar. Biol• (in press). Spies, R. B., Rice, D. W., Montagna, P. A., Ireland, R. R., Felton, .1. S., Healy, S. K. & Lewis, P. R. (1985). P¢~llutant bodv burdens and reproduction in I'latici~thvs stellams from San Francisco Bav. Report UCII) 19993-84 from the Law,ence Livcrmore National Laboratery for the National Oceanic and Atmospheric Administration, Rockville, Maryland, USA. Stephcnson, M. D., Smith, D., lchikawa. G., Goetzl, J. & Martin, M. (1986). State Mussel Watch Program: Preliminary Data Report, 1985-1986. Report of the California Department of Fish & Game to the State Water Resources Control Board, Sacramento, California, USA. Stevens, D. E. (1979). Environmental factors affecting striped bass (Morotte saxatilis) in the Sacramento-San Joaquin estuary. In San Frattcis£'o Bay. 7he Urbanized Estua~ (T. J. Conomos, ed.), pp. 469478. American Association for the Advancement of Science, San Francisco. Stevens, D. E. (1980). Factors affecting the striped bass fisheries of the west coast. In Marine Recreational Fisheries (H. Cleppcr, ed.), pp. l 5-28. Sport Fishing Institute, Washington, D.C. Stevens, D. E., Kohlhorst, D. W., Miller, L. W. & Kelley, D. W. (1985). The decline of striped bass in the Sacramcnto-San Joaquin estuary California. Trans. Ame~: Fish. Soc. 114, 12-30. SWRCB (1981). Toxic Substances Monitoring Program, 1980. Water Quality Monitoring Report No. 81-8TS. State Water Resources Control Board, Sacramento, California, USA. SWRCB (1986). Toxic Substances Monitoring Program, 1984. Water • Quality Monitoring Report No. 86-4-WQ. State Water Resources Control Board, Sacramento, California, USA. Tanabe, S., Tatsukawa, R. &. Phillips, D. J. H. (Iq~87). Mussels as bioindicators of PCB pollution: a case study on uptake and release of PCB isomers and congeners in green-lipped mussels (Pema viridis) in Hong Kong waters. Environ. Pollut. 47, 41-62. U.S. EPA (1974). Shellfish Study of San Francisco Bay, April-June 1972. Technical Report EPA-909/9-74-003, U.S. Environmental Protection Agency, Washington, D.C. Von Westernhagen, H., Rosenthal, H., Dethlefsen, V., Ernst, W., Harms, U. & Hansen, P.-D. (1981). Bioaccumulating substances and reproductive success in Baltic flounder Ptatichthys flesus. Aquatic Toxicol. 1, 85-99. Whipple, J. A., Crosby, D. G. & Jung, M. (1983). Third Progress Report, Cooperative Striped Bass Study. Special Projects Report No. 83-3sp, State Water Resources Control Board, Sacramento, California, USA. Wild, P. W. & Tasto, R. N. (1983). Life history, environment, and marlculture studies of the Dungeness crab, Cancer rnagister, with emphasis on the central California fishery, resources• Calif. Fish & Game Fish. Bull. 172, 5-360.

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