Chemical and toxicological characteristics of sewage sludge ocean dumped in the New York Bight

Marine Pollution Bulletin 0025-326X/87 $3.00+0.00 © 1987 Pergamon Journals Ltd.

Marine Pollution Bulletin, Volume lg, No. 7, pp. 394-399, 1987. Pnnted in Great Britain,

Chemical and Toxicological Characteristics of Sewage Sludge Ocean Dumped in the New York Bight EDWARD D. SANTORO, ** and THOMAS J. FIKSLIN + * US EPA Region II, Marine and Wetlands Protection Branch, 26 Federal Plaza, New York, N Y 10278, USA t US EPA Region II, Environmental Services Division, Woodbridge Avenue, Edison, NJ 08837, USA ~Present address: William E Cosulich Associates, 3000 Hadley Road, South Plainfield, NJ 07080, USA

This paper compares and contrasts data on the chemical characteristics and acute toxicities of the waste from nine applicants (representing 20 sewage treatment facilities) currently disposing of municipal sewage sludge at the 12-Mile dumpsite located in the New York Bight Apex. Each of the chemical analytes examined for the 20 facilities was highly variable, both within and among facilities. Toxicity tests conducted by the applicants revealed that, in the majority of tests, Mysidopsis bahia was the most sensitive of the three species tested. Five facilities that receive large volumes of industrial waste were found to contribute over 75% of the total toxic load to the dumpsite.

Existing Regulatory Criteria The US Marine Protection, Research and Sanctuaries Act (MPRSA) requires that toxicity tests and quantitative chemical constituent limits serve as two major facets in the regulation of ocean dumping activities. The final determination as to the environmental acceptability of a proposed discharge is based on the results of laboratory tests, the total volume to be dumped, characteristics of initial mixing, dispersion and diffusion at the dump site, and the condition of the dump site--particularly whether there are organisms present at the dump site which are likely to be affected by the dumped material. For bulk discharges of liquids, solids, or mixtures of liquids and solids, the primary regulatory tests performed by the applicants are acute bioassays of the liquid, suspended particulate, and solid phases, if present. The liquid and suspended particulate phase bioassays are run for 96 h on three groups of organisms: plankton, crustacea, and fish. According to the regulatory standard, the concentration within the zone of initial mixing must be reduced within four hours after dumping to less than 0.01 of the lowest LCs0 or ECs0 determined for the most sensitive species tested. Also, within the same time period, marine water quality criteria (which are chemicalspecific) established by the US Environmental Protection Agency must be met. 394

The US Environmental Protection Agency (US EPA, 1984) has recently proposed that both biological (toxicity tests) and chemical methods be used to assess the effect of complex mixtures discharged from industrial and municipal sources on water quality and aquatic communities. Toxicity tests are specifically emphasized since no other method can assess the combined effects of the various chemical components of complex mixtures.

Assessment of Waste Impacts An emerging view in the field of marine pollution science is the need to perform holistic assessments of pollution effects. It has been argued by O'Connor & Swanson (1982) and White & Champ (1985) that there is no evident relationship between toxicity tests and protection against any particular degree of ecosystem impact. Researchers in the field of marine pollution have usually examined specific toxic effects of one or two contaminants and chronic or sub-lethal effects of pollutants on selected parameters (i.e., reproductive rate, respiration rate etc.) in single species. In these cases, extrapolation of the toxic effect to population level impacts is often hypothetical or non-existent. Sullivan & Ritacco (1985), however, found that laboratory bioassays using the copepods Acartia tonsa and Acartia hudsonica correctly predicted trends of high and low mortality concurrently observed in mesocosms; although the actual mortality rates were different. Miller et al. (1985) concluded that the existing bioassay methods and test organisms are satisfactory to characterize acute toxicities of sewage sludge samples from three treatment plants currently ocean dumping in the New York Bight Apex. Swartz et al. (1984), however, tested the toxicity (10 day LCso) of sludge sediment mixtures to a marine amphipod, and noted that rank correlations between toxicity and specific chemicals were usually not significant. They attributed this to different combinations of stress involving multiple or unmeasured factors for the observed effects. The present paper presents correlations between toxicity

Volume 18/Number 7/July 1987

and specific chemical analytes in municipal sewage sludges ocean dumped in the New York Bight Apex.

TABLE 1 Municipal Sewage Sludge Ocean Dumping Applicants in US EPA Region II.

Methods

Applicant

Chemicals and acute toxicity testing was conducted by the respective applicants as part of their permit requirements. The frequency of testing required by the permits was generally four times per year, although the testing of sludge samples from the New York City facilities was performed only once in 1982 and 1985, and semiannually in 1983 and 1984. Testing was conducted monthly during 1984 and 1985 by MCUA (see Table 1 for abbreviations of applicants). Quarterly testing was conducted at the remaining facilities as follows: BCUA (1983-1985); JMEU (1984-1985); LRSA/RVSA (1983-1984); NCDPW (1985); and PVSC (19831985). All testing was performed in accordance with procedures detailed in EPA (1978) and EPA/COE (1978). The test organisms were the marine diatom, Skeletonerna costaturn, the mysid shrimp, Mysidopsis bahia, and the coastal finfish Menidia rnenidia. Tests are conducted with whole waste since, for the current ocean dumping applicants, a solid phase associated with sewage sludge has not been documented. Chemical analyses were performed utilizing standard EPA methods (US EPA, 1983) and Standard Methods (1980).

Bergen County Utilities Authority (BCUA,)

280 957

Joint Mccting of Essex & Union Counties (JMEU)

309 897

Results The nine ocean dumping applicants which generate municipal sewage sludges for ocean disposal are listed in Table 1 along with their 1985 sludge production. In 1985 these 9 applicants produced a total of 6.6 million metric tons which was disposed at the 12-Mile Sewage Sludge Dump Site in the New York Bight Apex (Santoro, 1987). Table 2 lists summary statistics for the common chemical constituents analysed in the sludge samples from each facility over the period 1982-1985 as well as for all facilities combined. It should be noted that sludge samples from the Linden-Rosetle Sewerage Authority and Rahway Valley Sewerage Authority were combined before analyses. Each of the analytes was highly variable over the period as evidenced by the high standard deviations. Of the plants listed, the PVSC facility contains the highest mean concentrations of mercury, arsenic, lead and chromium; the MCUA facility contains the highest mean concentrations for copper and zinc; while the LRSA/RVSA facilities had the highest mean concentration of cadmium. The highest mean concentration for vanadium was observed at the Port Richmond facility (NYCDEP), and the highest mean concentration for nickel occurred at the Tallman Island facility (NYCDEP). A summary of the results of whole waste toxicity tests are presented in Table 3 as the 96 h LCs0 for Mysidopsis bahia and Menidia menidia and EC50 in the case of Skeletonema costatum. In all cases, survival of control organisms was greater than 90%, otherwise the test

Sludge produced-- 1985 (metric tons)

Linden-Rosellc Sewerage Authority (LRSA)

85 970

Rahway Valley Sewerage Authority (RVSA)

1.69 729

Middlesex County Utilitics Authority (MCUA)

943 540

Nassau County Department of Public Works (NCDPW) (Bay Park Plant)

522 829

Passaic Valley Scwerage Commissioners (PVSC)

802 877

Westehester County Department of Environment Facilities (WCDEF) (Yonkers Plant)

426 688

New York City Department of Environmental Protection (NYCDEP)--(12 facilities) Coney Island Wards Island Hunts Point Owls Head 26th Ward Newtown Creek Tallman Island Bowery Bay Jamaica Bay Rockaway Beach Port Richmond Oakwood Beach

3 037 020

was deemed invalid. It can be noted from Table 3 that in most cases, Mysidopsis bahia was the most sensitive of the three species tested. However, on 17 occasions, Menidia menidia was more sensitive than either the mysid or the diatom. Those tests where Menidia exhibited a greater toxic effect contained statistically higher levels of TDS (dissolved solids) than those tests where mysids were more sensitive. Elevated concentrations of cadmium were also noted in the sludge samples in those tests; however, this result did not appear to be related either to the date or to a specific facility. With respect to individual facilities, sewage sludge samples from PVSC and Newtown Creek showed significantly greater toxicity to Menidia compared to the other facilities. PVSC, LRSA/RVSA and Newtown Creek sludge samples were also significantly more toxic to the mysid. These facilities are known to accept large volumes of industrial waste. Using 1985 data, relative toxic loadings for each of the facilities were determined as a function of the toxicity of the waste and the volume of sludge produced (Fig. 1). This toxic loading index was calculated for each facility by multiplying the volume of sludge produced by the average acute toxicity of the sludge samples to Mysidopsis bahia in toxic units. A toxic unit is a direct measure of toxicity derived by dividing the LCs0 or ECs0 into 100. As indicated in the figure, five facilities (BCUA, MCUA, LRSA/RVSA, and PVSC) contribute greater than 75% of the total toxic load. Pearson product-moment correlation coefficients were calculated for the combined chemical constituent data versus the acute toxicity data for all three test species. The significant correlation coefficients are presented in Table 4 for all facilities. Menidia menidia toxicity data exhibited the strongest negative correlations with total chromium and the two metal sum indices. Toxicity of sludges to Mysidopsis bahia was also 395

Marine Pollution Bulletin TABLE 2

Chemical Characteristics of Municipal Sewage Sludge Ocean Dumped in EPA Region II. For each facility, the mean parameter values (parts per million) are shown with the (standard deviation) and number of analyses. Facility

COD

TSS

Oil & Grease

Petro. Hydro.

Hg

Cd

As

Pb

Cu

Zn

Cr Total

Ni

Vn

Middlesex County

40770 33496 (10693) ( 2 9 0 1 ) 22 21

1260 (476) 23

447 (178) 23

0.07 (0.04) 21

2.5 (1.2) 21

0.16 (0.08) 20

64.2 (37.9) 21

128.4 (37.9) 21

351.9 (98.6) 21

5.6 (1.3) 21

1.9 (0.4) 21

0.5 (0.2) 20

Passaic Vallcy

86507 79965 (20037) (32433) 12 12

9033 (7467) 12

6648 (7154) 12

1.26 (1.12) 12

7.3 (5.0) 12

2.10 (3.05) 12

317.8 (247.4) 12

114.7 (47.3) 12

136.7 (75.1) 12

140.2 (69.3) 12

12.6 (3.3) 12

3.0 (3.2) 12

LRSA/ RVSA

32842 26481 (17480) (16404) 9 8

3438 (2824) 8

3059 (2396) 8

0.20 (0.19) 8

10.3 (27.4) 8

0.23 (0.28) 8

22.9 (16.6) 8

59.0 (40.7) 8

120.2 (79.6) 8

43.9 (43.3) 8

18.9 (14.4) 8

2.8 (4.0) 8

Bergen County

28364 24310 (10930) (10231) 13 13

3271 (3038) 13

1951 (1428) 14

0.14 (0.09) 14

3.(I (2.7) 14

0.20 (0.22) 14

12.1 (8.4) 14

57.7 (40.3) 14

64.5 (40.2) 14

30.1 (16.6) 14

15.4 (9.6) 14

6.1 (11.2) 14

Joint Mtg. Essex& Union

47239 (7847) 8

35915 (18173) 8

4416 (1538) 8

2734 (247) 8

0.29 (0.25) 9

4.3 (4.7) 9

0.25 (0.14) 9

13.7 (10.3) 9

47.3 (27.7) 9

78.0 (58.5) 9

29.7 (25.4) 9

14.9 (11.6) 9

6.0 (4.5) 9

Nassau Co. (Bay Park)

8919 17462 (12185) (28889) 5 5

1067 (1069) 5

629 (817) 5

0.06 (0.06) 5

0.23 (0.14) 5

0.03 (0.02) 5

2.7 (2.3) 5

7.4 (5.1) 5

12.1 (6.6) 5

1.7 (0.8) 5

1.4 (0.9) 5

4.6 (4.0) 5

Port Richmond

25157 (15320) 7

26471 (8840) 7

1884 (948) 7

942 (591) 7

0.11 (0.11) 7

0.49 (0.23) 7

0.69 (0.26) 7

19.3 (5.1) 7

50.9 (18.3) 7

48.4 (14.6) 7

2.2 (1.0) 7

3.9 (0.8) 7

12.2 (29.9) 7

26th Ward

28725 (18857) 6

25217 (8943) 6

2826 (1852) 6

1496 (1330) 6

0.09 (0.05) 6

1.05 (0.24) 6

0.78 (0.38) 6

20.7 (10.7) 6

69.5 (26.7) 6

71.3 (26.2) 6

24.0 (15.9) 6

6.1 (3.6) 6

0.9 (0.4) 6

Oakwood Beach

14113 (6765) 6

16037 (10631) 6

1253 (743) 6

607 (481) 6

0.08 (0.09) 6

0.37 (0.24) 6

0.30 (0.18) 6

7.2 (4.2) 6

24.8 (14.3) 6

21.7 (11.7) 6

1.3 (1.4) 6

3.3 (2.0) 6

0.8 (0.1) 6

Westchestcr County

23891 (3263) 5

22398 (7254) 5

2157 (725) 5

1556 (549) 5

0.13 (0.04) 5

0.38 (0.10) 5

0.07 (0.05) 5

13.4 (4.2) 5

48.0 (17.1) 5

4(/.3 (16.1) 5

4.4 (1.9) 5

4.4 (1.7) 5

0.6 (0.2) 5

Wards Island

27579 18067 (12171) ( 8 4 1 5 ) 6 6

1963 (1304) 6

1078 (857) 6

0.09 (0.05) 6

0.33 (0.08) 6

0.45 (0.28) 6

20.7 (9.1) 6

52.7 (14.9) 6

35.1 (21.0) 6

11.7 (4.1) 5

2.0 (0.4) 5

1.I (0.4) 5

Tallman Island

23417 (3855) 6

17250 (9531) 6

1212 (626) 6

570 (340) 6

0.14 (0.08) 6

1.02 (0.32) 6

0.51 (0.13) 6

13.3 (5.2) 6

43.2 (13.4) 6

38.2 (11.4) 6

27.1 (34.0) 6

20.0 (10.5) 6

0.9 (0.3) 6

Rockaway

30053 29183 (18235) (11307) 6 6

2403 (1424) 6

909 (414) 6

0.18 (0.12) 6

0.44 (0.16) 6

0.84 (0.15) 6

17.3 (3.5) 6

115.8 (96.4) 6

55.7 (38.7) 6

3.7 (0.7) 6

1.8 (0.7) 6

1.1 (0.3) 6

Owlshead

25030 28120 (17229) (18090) 6 6

4403 (3971) 6

1941 (2033) 6

0.10 (0.09) 6

0.71 (0.45) 6

0.65 (0.50) 6

22.2 (22.6) 6

40.5 (32.9) 6

52.0 (34.4) 6

9.3 (11.8) 6

4.5 (4.3) 6

1.0 (0.6) 6

Newtown Creek

40942 26383 (19745) (16238) 6 6

3216 (2393) 6

1799 (1320) 6

0.20 (0.13) 6

6.1 (2.4) 6

1.15 (0.49) 6

79.3 (45.4) 6

116.8 (47.6) 6

143.5 (52.7) 6

118.7 (55.4) 6

15.8 (6.7) 6

2.1 (0.5) 6

Jamaica

20275 (7062) 6

16117 (4700) 6

1768 (783) 6

759 (357) 6

0.10 (0.14) 6

0.60 (0.34) 6

0.47 (0.11) 6

12.1 (4.2) 6

39.7 (5.4) 6

34.7 (6.2) 6

8.0 (2.0) 6

2.6 (0.7) 6

1.0 (0.3) 6

Hunts Point

32367 26383 (17216) (13445) 6 6

2490 (2294) 6

1553 (1651) 6

0.08 (0.04) 6

0.81 (0.I9) 6

0.62 (0.25) 6

15.0 (8.8) 6

51.7 (13.9) 6

52.8 (15.8) 6

15.1 (4.0) 6

4.8 (1.1) 6

1.1 (0.3) 6

Coney Island

71233 54980 (55101) (31617) 6 5

6349 (6591) 6

4381 (5562) 6

0.28 (0.31) 6

0.67 (0.56) 6

1.12 (1.29) 6

44.1 (47.8) 6

91.7 (96.6) 6

86.5 (103.6) 6

17.7 (22.2) 6

10.7 (11.7) 6

2.2 (2.6) 6

Bowery Bay

22163 20717 (12015) (10632) 6 6

2370 (1120) 5

1179 (825) 6

0.10 (0.05) 6

1.3 (0.7) 6

0.63 (0.37) 6

21.7 (10.6) 6

81.3 (46.5) 6

120.8 (77.3) 6

37.6 (23.7) 6

6.3 (3.0) 6

1.2 (0.6) 6

36227 31101 25574 22252 147 144 635 624 126000 144847 70.5 71.6

3090 3673 146 11 25876 118.9

1884 2990 148 I 27001 158.7

0.23 0.46 147 0.002 4.10 201.0

2.64 6.90 147 0.06 78.10 261.4

0.59 1.00 146 0.009 11.40 179.0

73.3 53.0 147 1.0 312.0 72.3

112.0 119.0 147 1.6 562.0 106.2

31.1 48.4 145 0.1 285.6 155.6

8.3 8.8 145 0.5 41.0 106.2

2.8 7.8 145 0.2 80.0 282.0

Overall Mean STD N Minimum Maximum C.V. (%)

396

50.9 108.7 147 0.5 1009.2 213.6

Volume 18/Number 7/July 1987 TABLE 3 Mean Acute Toxicity Levels Associated with Municipal Sewage Sludge Samples (LCso for M. menidia and M. bahia, ECs0 for S. costatum).

40

Menidia menidia

Median Lethal or Effect Concentration (ppm) MaxiCoefficient N Mean Minimum imum of Variation 138 31 970 1100 165 000 75.7

Skeletonema costatum

139 158 618

7700

420 000

57.5

Mysidopsis bahia

139

54.0

42 000

79.2

35 Organism

A

12 620

F-

ABCDEFG

H I d K LM N O P O FGci/ities

Fig. 1 Relative Percent Toxic Loadings of the Facilities Currently Ocean Dumping Municipal Sludges in the New York Bight Apex, based on 1985 Sludge Production and Mean Acute Toxicity to Mysidopsis bahia. The respective facilities are as follows: A--BCUA, B--JMEU, C--LRSA/RVSA, D--MCUA, E--PVSC, F--NCDPW, G--WCDEF, H--Coney Island, l--Wards Island, J--Hunts Point, K--Owls Head, L--26th Ward, M--Newtown Creek, N--Tallman Island, O--Bowery Bay, P--Rockaway and Q--Port Richmond. No 1985 sludge production figures were available for Oakwood Beach or Jamaica.

negatively correlated to the two metal sum indices. Suspended solids was the most strongly correlated chemical analyte to the toxicity of the sludge samples to

TABLE 4 Significant Correlation Coefficients between LCs, and ECs0 for the three Species Tested and Chemical Parameters for All Sewage Treatment Plants. hi. menidia

Chemical Parameter Hg

r

S. costatum

(N)

-.28 (133)

r

(N)

-.33 (134)

M. bahia

r

(N)

-.23 (134)

Cd

-.19 (133)

NS ( 1 3 4 )

NS (134)

Pb

-.29 (133)

-.38 (134)

-.34 (134)

As

NS (133)

-.21 (134)

-.22 (134)

Cu

NS (133)

-.22 (134)

-.33 (134)

Zn

-.27 (133)

-.23 (134)

-.35 (134)

Cr

-.35 (131)

-.40 (132)

-.37 (132)

METSUMA*

-.32 (133)

-.38 (134)

-.43 (134)

METSUMBI

-.34 (131)

-.40 (132)

-.43 (132)

COD

-.18 (I33)

-.37 (134)

-.29 (134)

Skeletonema.

TS

-.24 (132)

-.39 (133)

-.29 (133)

Correlation coefficients were also computed for those five applicants having greater than 75% of the total toxic loading (Table 5). These correlations were much stronger than the correlations for all facilities combined for Menidia and Skeletonema. For these two species, significant increases in the correlation coefficients were noted for total chromium, copper, the two metal sum indices, and the conventional analytes COD, total solids and suspended solids, the correlation coefficients for Mysidopsis were generally lower and no longer significant for the non-metal analytes.

SS

-.29 (130)

-.42 (131)

--.32 (131)

Oil& Grease

-.25 (132)

-.26 (133)

-.24 (133)

Petroleum Hydrocarbons

-.26 (134)

-.23 (135)

-.26 (135)

p < 0.05; NS = Not Significant. *sum of metals: Pb, Cu, Zn. tsum of metals: Pb, Cu, Zn, Cr, Cd, Ni.

TABLE 5 Significant Correlation Coefficients between LCsos for Menidia menidia, Mysidopsis bahia and Skeletonema costatum (ECso) and Chemical Parameters for five Treatment Plants Contributing over 75% of the Total Toxic Load.

Discussion Contaminant characteristics

Segar et al. (1984) noted the importance of data on the variability of contaminants in municipal sewage sludge in assessing the impact of ocean disposal at a deepwater dumpsite. The chemical constituents of municipal sewage sludges examined in this study were highly variable, both in time and among plants, as evidenced by the high standard deviations and the high coefficients of variation (Table 2). In addition to the inherent variability associated with these materials, intermittent discharges from industrial sources into each treatment plant certainly affect loading of the contaminants in the sludges, O'Connor et al. (1985) presented earlier chemical data (1981) on municipal sewage sludge from the same facilities reported in this paper. Compared to those data the more recent testing showed higher average levels for copper, vanadium and arsenic; and lower levels for cadmium, mercury, lead, total chromium, zinc, and nickel.

M. menidia

Chemical Parameter

r

(N)

S. costatum

r

(N)

M. bahia

r

(N)

(42)

-.45 (42)

NS (42)

(42) (42) (42)

NS (42)

+.37 (42)

-.51 (42)

-.32 (42)

-.32 (42)

NS (42)

(42)

-.45 (42)

NS (42)

Cr

-.51 (42)

-.55 (42)

-.33 (42)

METSUMA*

-.50 (42) -.53 (42)

-.50 (42)

-.31 (42)

--.54 (42)

-.31 (42)

Hg Cd Pb As Cu

-.45 NS -.47 -.33 -.42

METSUMBt COD YS ss Oil & Grease Petroleum Hydrocarbons

-.54 (43) -.52 (42) -.52 (41)

-.64 (43)

NS (43)

-.58 (42)

NS (42)

-.61 (41)

NS (41)

-.31 (43)

-.39 (43)

NS (43)

NS (44)

--.30 (44)

NS (44)

p <0.05; NS=Not Significant. *sum of metals: Pb, Cu, Zn. "}sum of metals: Pb, Cu, Zn, Cr(T), Cd, Ni.

397

Marine Pollution Bulletin

Of the species tested, Mysidopsis bahia was the most sensitive organism tested, with LCs0s ranging from 0.005% to 4.2% (Table 3). These data are comparable to toxicities reported by Fava et al. (1985) for the NYCDEP facilities. LCs0s for the next most sensitive organism, Menidia menidia ranged from 0.11 to 16.5%. In approximately 88% of the tests, Mysidopsis was more sensitive than Menidia. Similar results were obtained for all plants. Miller. et al. (1985 and in press) noted that similar testing with the copepods Eurytemora herdmani and Pseudocalanus minutus showed even greater sensitivity to municipal sewage sludges, with LCs0s ranging from 0.03 to >0.8%. The copepods were more sensitive than mysids by a factor of 6 to 9 thus demonstrating the utility of this organism for future bioassay testing. Effects of Metals Trace metals are of ecological and toxicological interest because of their roles as micronutrients (Fe, Cu, Mn, Mo) and as toxicants (Cu, Hg, Si, Cr, Cd, Zn, Ni, Pb). Breteler (1984) discussed the classification of contaminants identified in the Hudson-Raritan Estuary with respect to human health and ecosystem concern, and identified three classes: Class A--immediate threat, Class B--potentially significant, requiring additional data collection, and Class C--low priority for ecosystem concern. Contaminants were grouped as follows: A=copper, mercury, and oil and grease; B=cadmium, lead, zinc, and silver; C=arsenic, chromium, nickel, and selenium. In the present study using municipal sewage sludges, the levels of the Class A contaminant copper averaged 73.3 ppm. This value is 3 to 4 orders of magnitude higher than acute toxicity values to sensitive marine species. The toxicity of copper has been primarily attributed to the cupric ion (Cu ++) and this highly reactive form is readily adsorbed onto the surface of particulates and complexed by dissolved organics. Although this should effectively reduce the toxic form of copper in the sludges, the levels of copper that are toxic to marine life are so low (acute values of 5.8 ppb top Mytilus, 40 ppb to Acartia spp., 70 ppb to Homarus americanus (US EPA, 1985)) that even a slight increase in cupric ion concentration in dilute solutions could produce acute toxicity to severaPmarine species. The issue of the complexing capacity of ocean waters in the New York Bight Apex for copper is presently under active investigation. The average level of mercury detected was 230 ppb. In seawater, mercury is generally present as an anionic complex (HgCO-) which does not adsorb readily to particulates (US EPA, 1980a). The criterion maximum concentration for saltwater is 3.7 ppb based on testing using the inorganic form HgC12. We believe that levels lower than this criterion would be reached rapidly during dumping operations. In class B, average zinc and lead concentrations were the first and third highest of the metals tested, respectively. Acute toxicity values for zinc for the most sensitive marine species are 2 to 3 orders of magnitude lower than the average levels detected (112 ppm) in the sewage sludge samples (US EPA, 1980b). The values 398

for the acute toxicity of zinc in that report are as follows: Acartia tonsa--290 ppb; Homarus americanus --321 ppb; and Mysidopsis--498 ppb. Although zinc is also readily adsorbed onto organic and inorganic particulates, desorption does occur as salinity increases (US EPA, 1980b). Acute values for lead are quite variable, ranging from 668 ppb for the copepod Acartia clausii to 2960 ppb for Mysidopsis bahia (US EPA, 1980c). The acute levels noted are 1 to 2 orders of magnitude lower than the average sludge concentrations (51 ppm). Both zinc and lead are, therefore, potential contributors to the observed toxicity noted in the present study. The additive effect of several metals on the observed toxicity of the municipal sewage sludges was investigated by calculating the correlation between the sum of several metals and the observed toxicity to the 3 test species. These values revealed that two metal groupings were significantly related to the acute toxicity to Menidia menidia and Skeletonema costatum (r < - 0 . 5 ; P < 0.01), and significantly but less strongly related to the acute toxicity to the mysid (r < -0.3; P < 0.05). The possibility for synergistic interactions of sludge constituents and their effect on the toxicity of the whole waste also needs further investigation. Macek (1975) reported greater than additive toxicity to freshwater fishes in 38% of tests using mixtures of several pesticides, including copper sulphate. It must be noted that an unknown portion of the toxic response to heavy metal contaminants is a function of the concentration of free metal ions, the presence of which is governed by a number of factors including pH, temperature, suspended particulates and dissolved organic materials. Effects of Oil and Grease and Petroleum Hydrocarbons Field investigations and short-term toxicity studies have demonstrated that oils and oil by-products are detrimental to aquatic organisms. For example, Swartz et al. (1984) noted that oil and grease concentrations were significantly correlated with survival of a marine amphipod, Rhepoxinius abronius, with more toxic sludges having an higher overall level of contamination. The toxicity of whole petroleum or of oil and grease is dependent upon the chemical composition of the mixture. One, two and three ring aromatics have been reported to be the most toxic components of petroleum (Breteler, 1984); however, generalizations of the toxic effect of petroleum compounds are difficult. Breteler (1984) notes that acutely toxic concentrations of petroleum hydrocarbons for adult marine organisms are in the range of 1 to 100 ppm. With more sensitive species, this value is approximately 0.1 ppm. When compared to whole sludge, these values are 1-2 orders of magnitude lower than those concentrations found in the present study. Correlations of both oil and grease and petroleum hydrocarbon concentrations with toxicity were generally somewhat lower than observed for certain metals (Tables 4, 5). Nonetheless, petroleum hydrocarbons and oil and grease may contribute to the observed overall toxicities. These constituents (and several of the metals previously discussed) would presumably be diluted to levels lower than the acute toxicity threshold soon after being discharged.

Volume 18/Number 7/July 1987

Effects of Particulates The confounding effect of particulate matter in interpreting Mysidopsis bahia toxicity tests has been brought into question by Fava et al. (1985) and Nimmo et al. (1982) concerning the utility of this species as a sensitive estimator of potential sewage sludge toxicity. Effects exhibited at the high concentrations of particulates existing in laboratory test conditions have been suggested to 1. dramatically alter direct chemical toxicity effects, and 2. produce mortality through mechanical disruption in a manner that may be dissimilar to actual field effects where suspended particulate concentrations are quickly reduced far below laboratory test concentrations. Data examined in the present study does show a correlation with conventional residue parameters (suspended or total solids) for all three test species (Table 4). Data summarized for those plants with greater than 75% of the toxic load, however, showed no correlation between these parameters and toxicity to mysids (Table 5). Although potentially confounded by multiple constituents, the proposition that toxicity to mysids may be due to particulates and not chemical constituents is not conclusively supported by the data presented in this paper. The authors thank D. C. Miller, D. A. Wolfe, and two anonymous reviewers for their helpful suggestions on this manuscript. This paper was presented at the Sixth International Ocean Disposal Symposium, 21-25 April 1986, at the Asilomar Conference Center, Pacific Grove, California.

Breteler, R. J. (ed.). (1984). Chemical Pollution of the Hudson-Raritan Estuary. NOAA technical memo. NOS/OMA 7. Rockville MD. Fava, J. A., Gift, J. J., Maciorowski, A. E, McCulloch, W. L. & Reisinger, H. J. II (1985). Comparative Toxicity of Whole and Liquid Phase Sewage Sludges to Marine Organisms. In Aquatic Toxicology and Hazard Assessment, Seventh Symposium. ASTM STP 854 (R. D. Cardwell, R. Purdy & R. C. Bahner, eds), pp. 229-252. American Society for Testing and Materials, Philadelphia. Macek, K. J. (1975). Acute Toxicity of Pesticide Mixtures to Bluegills. Bull. Environ. Contam. Toxicol. 14,648-652. Miller, D. C., Marcy, M., Berry, W., Deacutis, C., Lussier, S., Kuhn, A., Heber, M., Schimmel, S. C. & Jackim, E. (1985). Evaluation of Methods to Measure the Acute Toxicity of Sewage Sludge. US EPA Environmental Research Lab. Narragansett. Report # 671. Miller, D. C., Marcy, M., Berry, W., Deacutis, C., Lussier, S., Kuhn, A., Heber, M., Schimmel, S. C. & Jackim, E. (in press). The Acute Toxicity of Sewage Sludge to Marine Fish, Mysids and Copepods. In Oceanic Processes in Marine Pollution, Volume 5, Urban Wastes in Coastal Marine Environments (D. A. Wolfe & T. P. O'Connor, eds). R. E. Krieger Pub. Co., Malabar. Nimmo, D. R., Hamaker, T. L., Matthews, E. & Young, W. T. (1982).

The Long Term Effects of Suspended Particulates on the Survival and Reproduction of the Mysid Shrimp, Mysidopsis bahia, in the Laboratory. In Ecological Stress in The New York Bight: Science and Management (G. E Mayer, ed.), pp. 413-421. Estuarine Res. Federation. Columbia, South Carolina. O'Connor, J. S. & Swanson, R. L. (1982). Unreasonable Degradation of the Marine Environment--What is it? Oceans 1125-1132. O'Connor, T. P., Walker, H. A., Paul, J. F. & Bierman, V. J. (1985). A Strategy for Monitoring Contaminant Distributions from Proposed Sewage Sludge Dumping at the 106-Mile Disposal Site. Mar. Env. Res. 16,127-150. Santoro, E. D. (1987). Status report--phase out of ocean dumping of sewage sludge in the New York Bight Apex. Mar. Pollut. Bull. 18, 278-280. Segar, D. A., Stamman, E. & Davis, P. G. (1984). Criteria for the Development of a Monitoring Program for the North Atlantic Deepwater Municipal Sludge Site. Oceans 84 Conference. Wash. D.C. Sept. 10-12, 1984. Standard Methods (1980). Standard Methods for the Examination of Water and Wastewater, 15th Edition. American Public Health Assn American Water Works Association & Water Pollution Control Federation (Joint publishers). Washington, D.C. Sullivan, B. K. & Ritacco, P. J. (1985). Ammonia Toxicity to Larval Copepods in Eutrophic Marine Ecosystems: A Comparison of Results from Bioassays and Enclosed Experimental Ecosystems. Aquatic Toxicology 7, 205-218. Swartz, R. T., Schuhs, D. W., Ditsworth, G. R. & DeBen, W. A. (1984). Toxicity of Sewage Sludge to Rhepoxynius abronius, a marine benthic amphipod. Arch. Environ. Contain. & Toxicol. 13,207-216. US EPA (Unpublished). Information and data requirements under Section 102 of the Marine Protection Research and Sanctuaries Act for Municipalities applying for Special Ocean Dumping Permits to Dump Municipal Treatment Sludge into Ocean Water Governed by EPA Region II. US EPA (1978). Bioassay Procedures for the Ocean Disposal Permit Program, USEPA Environmental Research Laboratory. Gulf Breeze, Florida. EPA 600/9-78-010. US EPA/USA COE (1978). Ecological Evaluation of Proposed Discharge of Dredged Material into Ocean Waters; Implementation Manual for Section 103 of Public Law 92-532 (MPRS Act of 1972). Environmental Effects Laboratory, US Army Corps of Engineers, Waterways Experiment Station, Vicksburg, Mississippi. Appendices D and E. US EPA (1980a). Ambient Water Quality Criteria for Mercury. US Environmental Protection Agency, Washington, D.C. EPA 440/580-058. US EPA (1980b). Ambient Water Quality Criteria for Zinc. US Environmental Protection Agency, Washington, D.C. EPA 440/5-80079. US EPA (1980c). Ambient Water Quality Criteria for Lead. US Environmental Protection Agency, Washington, D.C. EPA 440/580-057. US EPA (1983). Methods for Chemical Analysis of Water and Wastes. US EPA Environmental Monitoring & Support Laboratory, Cincinnati, Ohio. EPA 600/4-79-020. US EPA (1984). Development of Water Quality Based Permit Limitations for Toxic Pollutants; National Policy. Federal Register 49 (48), 9016-9019. Friday March 9, 1984. US EPA (1985). Ambient Water Quality Criteria for Copper-1984. US Environmental Protection Agency. Washington, D.C. EPA 440/584-031. White, H. A. & Champ, M. (1982). The Great Bioassay Hoax and alternatives. In Hazardous and Industrial Solid Waste Testing: Second Symposium, pp. 200-312. ASTM Special Publication 805. Philadelphia, P.A.

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