HRMS analysis of mirex in soil of Liyang and preliminary assessment of mirex pollution in China

Chemosphere 79 (2010) 299–304

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HRGC/HRMS analysis of mirex in soil of Liyang and preliminary assessment of mirex pollution in China Bin Wang a,b, Fukuya Iino a,*, Gang Yu b, Jun Huang b, Yixin Wei c, Norimasa Yamazaki c, Jianfang Chen c, Xiaoli Chen c, Wei Jiang c, Masatoshi Morita d a

Institute for Sustainability and Peace, United Nations University, 53-70, Jingumae 5-chome, Shibuya-ku, Tokyo 150-8925, Japan Department of Environmental Science and Engineering, POPs Research Center, Tsinghua University, Beijing 100084, China CSD IDEA (Beijing) Institute of Environmental Innovation Co., Ltd., Beijing 100084, China d Department of Agriculture, Ehime University, 3-5-7, Tarumi, Matsuyama 790-8566, Japan b c

a r t i c l e

i n f o

Article history: Received 2 November 2009 Received in revised form 10 January 2010 Accepted 16 January 2010 Available online 7 February 2010 Keywords: Mirex Persistent organic pollutants Liyang HRGC/HRMS Fugacity model

a b s t r a c t China is a country with the most severe termite damage in the world. Mirex is one of the two effective orgochlorine pesticides used in China for termite control. A high-resolution gas chromatography/highresolution mass spectrometry (HRGC/HRMS) was employed for mirex analysis in soil samples from Liyang city, which once was an important mirex production base in China. The detected mirex levels in soil in Liyang were 2.9–4300 pg g1 dw (dry weight), with the geometric mean 26.83 pg g1 dw and the geometric standard deviation 5.02. The highest level occurred at the site near the Liyang Guanghua Chemical Factory. It implies the contribution of industrial activities to the mirex pollution in the surrounding environment. However, the factory only influenced very limited adjacent areas. A Level III fugacity model was developed to study the mirex pollution in Chinese provinces. The results show that the highest concentration occurred in Jiangxi Province, which has the largest consumption of mirex among Chinese provinces. On a regional scale, the calculated concentrations of mirex in the environment are generally so low that it indicates no harm to human and organisms. The total amount of mirex in the environment in China was estimated to be about 25.12 tons, most of which exists in soil. Ó 2010 Elsevier Ltd. All rights reserved.

1. Introduction China is a country with the most severe termite damage in the world. The termites concentrated mostly in the south of the Yangtze River and affect more than 40% of the total land area in China (GEF, 2006). Mirex is one of the two effective orgochlorine pesticides used in China for termite control. As one of the persistent organic pollutants (POPs) regulated by the Stockholm Convention (UNEP, 2001; Wong et al., 2005), its production and usage have been restricted in recent decades, due to the increasing evidence of its persistence in the environment, its tendency to accumulate in the food chain, its ability to travel a long distance and its toxicity to human and organisms (Kearney et al., 1999; Dai et al., 2001; Schell et al., 2004; Bloom et al., 2005; Jallad et al., 2006). In China, production of mirex began at the end of the 1960s. There were a total of seven mirex manufacturers in history. Mirex production was gradually stopped after 1975 and was restricted in the early 1980s. Due to serious termite damages in South China * Corresponding author. Tel.: +81 3 5467 1242; fax: +81 3 3406 7347. E-mail address: [email protected] (F. Iino). 0045-6535/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.chemosphere.2010.01.023

and shortage of cost-effective pesticides, some manufacturers resumed mirex production around 1986. In 2000, annual mirex output peaked at 31 tons. In 2004, the annual production capacity was about 677 tons, but only three manufacturers still produced mirex and the output was only about 10 tons (JS EPA, 2007). By the end of 2004, the accumulated mirex output was about 160 tons (GEF, 2006; Wei et al., 2007). In July 2006, the ‘‘Demonstration project of Alternatives to Chlordane and Mirex in Termite Control in China” was initiated to eliminate the production and usage of mirex. However, China did not completely eliminate the production and use of mirex until May, 2009. In China, all the mirex manufacturers are located in Jiangsu Province, which lies in the downstream area of the Yangtze River. Liyang Guanghua Chemical Factory (LGCF), located in Liyang city, Jiangsu Province, once was a major mirex supplier with the largest mirex production capacity in China. However, the pollution status of mirex in Liyang city has not been studied and reported. Chemical analysis can provide important information on mirex pollution. However, such information is still very scarce in China. In order to evaluate the mirex pollution status in China, comprehensive monitoring in the whole China seems to be necessary. However, it needs massive manpower, material and financial

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resources. Developing suitable models to estimate the pollution status of mirex in China is a feasible alternative to fill the data gap. In this study, Liyang was selected as a typical case, where soil samples were taken for mirex analysis using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/ HRMS) method because mirex is usually undetectable using a GC/MS method due to its low concentration in the environment. Then, a Level III fugacity model was developed to simulate the fate and evaluate the general pollution status of mirex in Chinese provinces. 2. Materials and methods 2.1. Mirex analysis in soil in Liyang, Jiangsu Province 2.1.1. Sampling Liyang city is located in the south of Jiangsu Province, between north latitude 31°100 –31°410 , east longitude 119°080 –119°360 . The total area of Liyang is 1535 km2. The sampling sites and land types are shown in Fig. 1 and Table 1. DIK-115B soil sampler (Daiki, Japan) was used for sampling. In February, 2009, 16 soil samples (Nos. 1–16) were respectively taken from the 16 grid units (Fig. 1). In the vicinity of the mirex producer (LGCF), seven other samples (Nos. 17–23) were collected. In total, 23 soil samples were immediately transferred to the laboratory and kept at 20 °C in the refrigerator until extraction. 2.1.2. Sample preparation The soil samples were freeze-dried in a vacuum freezing drier (EYELA FDU-1100, Japan), milled and then passed through a 10 mesh sieve (the aperture 2 mm). Twenty grams of soil samples were weighed out into a glass-fiber thimble (40  120 mm), and then spiked with 50 lL of cleanup standard solution (10 pg lL1 of 13C-Mirex in nonane, Cambridge Isotope Laboratories). The sample was extracted with 300 mL of toluene for at least 16 h. After Soxhlet extraction, the extract was concentrated to 2 mL using a rotary evaporator (EYELA, Japan), and transferred into 100 mL of hexane for solvent exchange. The sample was then treated with sulfuric acid to remove its color and interferences. After that, the sample was washed with water till the neutral pH value was reached, and finally was dehydrated using anhydrous sodium sulfate.

After the sulfuric acid treatment, the sample was concentrated to 2 mL using a rotary evaporator (EYELA, Japan), and applied to a multilayered-silica-gel column, which was packed from bottom to top with 0.9 g of silica gel, 3 g of 2% KOH, 0.9 g of silica gel, 4.5 g of 44% sulfuric acid gel, 6 g of 22% sulfuric acid gel, 0.9 g of silica gel, 3 g of 10% silver nitrate silica gel, and 6 g of anhydrous sodium sulfate. It was then eluted with 200 mL of hexane to remove interferences, such as sulfur, moisture, organic matter, and proteins. The sample was concentrated to 2 mL using a rotary evaporator (EYELA, Japan), and then was transferred to a blowdown vial to be concentrated to almost dryness with a nitrogen blowdown device (EVAN-kd, Japan). Then, 50 lL of syringe spike solution (2 pg lL1 of 13C-1,2,3,4-TeCDD in nonane, Cambridge Isotope Laboratories) was added. After the sample dissolved, it was transferred into a sample vial and placed in a refrigerator until HRGC/HRMS analysis. 2.1.3. HRGC/HRMS analysis A HRGC/HRMS (Agilent 6890 N/JEOL JMS-800D) was employed to determine mirex in the samples. The inlet temperature of GC was 250 °C; sampling mode was splitless sampling; sample size was 1.5 lL; the temperature program for GC oven was set as follows: initial temperature 130 °C, and held for 1 min; increased to 180 °C at the rate of 15 °C min1, held for 0 min, and then increased to 310 °C at the rate of 3 °C min1 and held for 5 min. The column was RH12 ms (60 m  0.25 mm i.d.). The MS was operated at a resolution of >10 000 under SIM mode. Ion source temperature was set as 300 °C. The temperature of GG–MS interface was set as 300 °C. Ionization electric current was 500 lA; EI source voltage was 38 eV; ion acceleration voltage was 10 kV; mass correction mode was Lock Mass mode (PFK). The following ions (m/z) were selected for quantification: mirex 271.8102, 273.8072 (13C 276.8269, 278.8240) and 1,2,3,4-TeCDD 319.8965, 321.8936 (13C 331.9368, 333.9339). 2.2. Fugacity model analysis of mirex pollution in China 2.2.1. Multimedia fugacity model A Level III multimedia fugacity model was developed and applied to simulate the fate of mirex based on an approach of Mackay and Paterson (1991). Four bulk compartments including air (air and particulates), water (water, suspended solids, and fish), soil (air, water, and solids), and sediment (water and solids) were

Fig. 1. Sampling sites in Liyang, Jiangsu Province, China (Site 23 is 50 m away from the Liyang Guanghua Chemical Factory).

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B. Wang et al. / Chemosphere 79 (2010) 299–304 Table 1 Mirex levels in soil in Liyang, China. No.

Location

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Longitude

Latitude 0

0

119°27.11 E 119°25.320 E 119°17.720 E 119°20.050 E 119°14.270 E 119°12.310 E 119°13.240 E 119°16.410 E 119°19.710 E 119°18.620 E 119°19.230 E 119°25.710 E 119°29.380 E 119°26.530 E 119°26.030 E 119°33.450 E 119°30.830 E 119°29.640 E 119°29.470 E 119°28.710 E 119°28.520 E 119°27.570 E 119°29.440 E

Longjian Hill Pingqiao Shezhu Gucheng Meizhuhe Yangqiao Shangpei Shangxin North Zhuze Dashankou Reservoir Zhongqiao Village Tianmu Lake Daibu Dachengqiao Bieqiao Shanghuang Lutou Xiazhuang Shitang Yangzhuang Niezhuang Fangli Village Guanghua Chemical Factory

31°15.85 N 31°13.180 N 31°19.670 N 31°21.890 N 31°19.420 N 31°23.510 N 31°29.200 N 31°31.900 N 31°33.960 N 31°38.280 N 31°27.820 N 31°19.700 N 31°19.120 N 31°27.720 N 31°34.100 N 31°33.050 N 31°29.150 N 31°28.110 N 31°29.690 N 31°29.250 N 31°28.720 N 31°29.230 N 31°28.780 N

included. The fugacity model was developed as follows (Wang, 2009):

E i þ Ai þ

X

Dji fj  Gi Z i fi  V i Z i K i fi 

X

Dij fi ¼ 0

ð1Þ

where Ei is emission rate into the compartment i; Ai is advection input to the compartment i; Dji is transfer coefficient from compartment j to compartment i; fi is fugacity of the compartment i; Gi is the volume velocity of compartment i; Zi is fugacity capacity of the compartment i; Vi is the volume of the compartment i and Ki is reactive coefficient or the compound in the compartment i. Compartments air, water, soil, and sediment were indicated by 1, 2, 3, and 4, respectively. Eq. (1) can be transformed into a matrix form (Bru et al., 1998; Li et al., 2006; Wang, 2009):

Af þ U ¼ 0

ð2Þ

where f is the solution matrix (fugacity matrix), A is the fate matrix and U is the emission rate matrix:

0

1 f1 Bf C B 2C f ¼ B C; @ f3 A

0

ðE1 þ G1 C B1 Þ=V 1 Z 1

Land type

CMirex (pg g1 dw)

Tree-planting land Vegetable land Cropland Vegetable land Alley Vegetable land Wasteland Ridge of field Cropland River bank Vegetable land Tree-planting land Vegetable land River bank Ridge of field Cropland Wasteland Cropland Cropland Alley in the field Wasteland Ridge of field Cropland

69 7.6 5.1 9.3 41 9.9 3.5 66 18 9 19 17 52 6.4 11 2.9 140 50 22 220 76 50 4300

2.2.2.1. Physico-chemical properties of mirex. The physico-chemical properties of mirex mainly came from Mackay et al. (2006), or calculated from EPI suit v3.0 of USEPA. The main physico-chemical properties (25 °C) used here included: molecular weight (MW) 545.55, water solubility 0.085 mg L1, vapor pressure (VP) 8.00  107 mm Hg, octanol–water partition coefficient (log Kow) 6.89, and the half lives in air, water, soil and sediment were 170, 170, 55 000 and 55 000 h, respectively. Henry’ Law constant (H) and air–water partition coefficient (log KAW) were calculated from vapor pressure. Octanol–air partition coefficient (KOA) was calculated as the quotient of Kow and KAW (Kow/KAW). Kow, KAW and KOA were adjusted to the mean annual temperature in each province using conventional van’t Hoff equations.

2.2.2.2. Environmental characteristics. The environmental parameters were mainly adopted from Wang (2005), Mackay (2001), Natural resources database of China (http://www.naturalresources.

1

B ðE þ G C Þ=V Z C 2 B2 2 2C B 2 U¼B C @ A E3 =V 3 Z 3

0 f4 ðD12 þ D13 þ G1 Z 1 þ DR1 Þ=V 1 Z 1 B D12 =V 2 Z 2 B A¼B @ D13 =V 3 Z 3 0

0

D21 =V 1 Z 1

D31 =V 1 Z 1

0

ðD21 þ D24 þ G2 Z 2 þ DR2 Þ=V 2 Z 2

D32 =V 2 Z 2

D42 =V 2 Z 2

0

ðD31 þ D32 þ DR3 Þ=V 3 Z 3

0

D24 =V 4 Z 4

0

ðD42 þ DA4 þ DR4 Þ=V 4 Z 4

Using Matlab, the fugacity fi and the general mirex concentration Ci = fi  Zi in every compartment was calculated. 2.2.2. Data acquisition The environment-related properties of mirex, environmental parameters and mirex emission data were acquired for the model calculation.

1 C C C A

csdb.cn) and statistic yearbooks of Chinese provinces. The important environmental data included: annual average temperature, total surface area, water area, average air height, average water depth, average soil depth, average sediment depth, Coastline length, average depth of costal water, average width of costal water, volume fractions of particles in air, volume fractions of particles in water, volume fractions of fish in water, volume fractions

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Table 2 Mirex consumption and the estimated amount of mirex in environmental matrices. Province

Anhui Fujian Guangdong Guangxi Hubei Hunan Jiangsu Jiangxi Liaoning Shaanxi Shanghai Sichuan Zhejiang Chongqing Total a

Consumptiona (kg)

Amount of mirex in environmental matrices Air (kg)

Sediment (kg)

57.4 426.6 290 622.6 98.6 95 51.4 857.8 23.6 2 16.4 27.8 173.8 85.6

1.32  105 1.04  104 4.34  105 9.56  105 4.71  105 2.46  105 3.49  105 2.73  104 4.82  106 1.93  107 6.65  106 3.17  106 3.65  105 1.48  105

1.4517 6.6155 1.0647 4.5266 5.731 2.2273 5.0617 25.795 1.3951 0.01493 0.8386 0.1781 3.4898 1.0262

2828.6

7.02  104

59.4161

Soil (kg)

Water (kg)

508.47 3778.8 2568.7 5515 873.43 841.52 455.32 7598.5 209.07 17.717 145.28 246.26 1539.6 758.25

Sum

0.02852 0.2247 0.1637 0.3442 0.03877 0.04766 0.01378 0.4131 0.009342 0.001104 0.006813 0.01544 0.08915 0.04606

25055.92

509.95 3785.64 2569.93 5519.87 879.20 843.79 460.40 7624.71 210.47 17.73 146.13 246.45 1543.18 759.32

1.4423

25116.78

The average annual consumption from 1997 to 2001 (GEF, 2006).

6

of air in soil, volume fractions of water in soil, volume fractions of solids in soil, volume fractions of pore water in sediment, volume fractions of solids in sediment, and various environmental transportation velocities. In absence of reliable literature data, default values were taken from Mackay (2001).

4

Frequency

2.2.2.3. Mirex emission. The mirex emission into the environment was assumed to be the mirex consumption. Among the termite-affected provinces in China, only the following ones listed in Table 2 used mirex for termite control in recent years. It was supposed that 100% of the consumed mirex was applied to the soil because it was only used for termite control in China. Therefore, in the model, the average annual mirex consumption (Table 2) was used as mirex emission rate into the soil matrix.

5

3 2 1 0 -1

0

1

2

3

4

log C Mirex 3. Results and discussion Fig. 2. Distribution of mirex in soil in Liyang.

3.1. Detected mirex levels in soil 3.1.1. Comparison of mirex levels The detected mirex levels in the soil samples are listed in Table 1. The detected levels of mirex in the soil samples were 2.9–4300 pg g1 dw, which were much lower than the primary remediation target for mirex in soil for nine districts of USA (270 ng g1 for residential areas, 960 ng g1 for industrial areas). The highest level, 4300 pg g1 dw, occurred at the site near the LGCF, which has produced mirex for more than 10 years. It implies the contribution of industrial activities to the mirex pollution in the surrounding environment. At Site 20, which is located at the 2 km leeward from the LGCF, the second highest mirex level, 220 pg g1 dw, was observed. The mirex level decreased to 50 pg g1 dw at the Site 22, which is 4 km leeward from the factory. For the four sites 2 km away from the factory in different directions (2 km east, south, west, north of the LGCF), the concentrations were 22–140 pg g1 dw, with a geometric mean of 58.49 pg g1 dw, which were significantly higher than those in the soil samples from the 16 grids (Nos. 1–16). To our knowledge, in the published articles, HRGC/HRMS method, which provides a more sensitive analysis than a GC/MS method, has never been used for mirex analysis in soil in China. In most cases, the detection ratio of mirex in environmental media is very low using GC/MS methods due to its low concentration (Chan et al., 1999; Jiang et al., 2005; Oh et al., 2005; Cornish et al., 2007; Wang et al., 2007,2008; Chen et al., 2008; Shi et al. 2008). Using a GC/MS method, Limit of Detection (LOD) is usually about 0.01 ng g1 dw;

Limit of Quantification (LOQ) is about 0.1 ng g1 dw. In this study, a HRGC/HRMS was employed in mirex analysis, and mirex was detectable in all the soil samples. The LOD is 0.125 pg g1 dw, the LOQ is 0.5 pg g1. The recovery rate is 73–111%. In China, because mirex consumption is not very large, the mirex levels in the environment are usually so low that GC/MS is not applicable to mirex analysis, and as such HRGC/HRMS is preferable. 3.1.2. Statistical distribution of mirex in soil Kolmogorov–Smirnov (KS) test was performed to determine if the normal or lognormal model was applicable for fitting the spatial distribution of detected mirex levels in soil in Liyang city (SPSS v13.0). It shows that the mirex levels generally obeyed lognormal distribution (Kolmogorov–Smirnov Z = 0.618, Asymp. Sig. (2tailed) = 0.840) (Fig. 2). The geometric mean was 26.83 pg g1 dw and the geometric standard deviation was 5.02. Fig. 2 shows that the mirex level at one site is very high, which is an obvious outlier. It is the site 50 m away from LGCF, which is sure to be significantly influenced by the adjacent industrial activities. 3.1.3. Contour of mirex levels in soil The mirex levels obeyed the lognormal distribution, so the logarithm of concentrations of mirex were calculated and used for contour analysis (Fig. 3). The contour map of mirex levels (Fig. 3) indicated that the LGCF was the point pollution source with highest mirex level in its surrounding area. The South and Northwest might be partially affected by the transportation from the LGCF

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A

3.5 3.3 3.1 2.9 2.7 2.5 2.3 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0.7 0.5 0.3 0.1

North Latitude

31.5

31.4

31.3

31.2

31.1 119.1

119.2

119.3

119.4

119.5

1000 100 10 1 0.1 0.01 0.001 0.0001 0.00001 0.000001 0.0000001

Soil ( pg g-1) Sed ( pg g-1 ) Water ( pg mL-1 ) Air ( pg m-3 )

Jia n gx F uj i S ha ia n ng Gua hai ng Z h xi Gua e jia ng ng d Cho o ng ng q in Jia n g gsu Hub e H un i an Anh L ia ui o ni S ich ng u S ha a n anx i

31.6

Concentration

31.7

Province

B

119.6

East Longitude Fig. 3. Contour of mirex levels (log CMirex, pg g1) in soil in Liyang (Kriging interpolation method was applied).

because the prevailing wind is east wind in summer; and north wind in winter. However, the influenced area and the extent to which it is influenced are rather limited. 3.2. Estimated mirex pollution in China The results from the Level III Fugacity model were compared with those of ChemCAN model. The results were comparable to each other because the models were developed based on the same principles and method. Then, the observed concentrations were used for model validation. Based on the model, the calculated mirex level in Jiangsu Province was 18.06 pg g1 in soil. If the Site 23 near the LGCF was not taken into consideration, the geometric mean was 21.30 pg g1 for detected mirex in soil. If only the 16 sites (Nos. 1–16) were applied, the geometric mean of the detected mirex level was 13.55 pg g1 in soil. The calculated soil level in Jiangsu Province appropriated the statistical value of these observed values. It indicates the applicability of the model to calculate the general mirex pollution levels. Although all mirex was produced in Jiangsu Province, the industrial activities did not bring heavy pollution in Jiangsu Province. Mirex production only influenced very limited area surrounding the factory. The possible reasons are as follows: (1) In China, the main pesticide used for termite control is chlordane. The production of mirex is not very large (Yu et al., 2005; GEF, 2006). (2) In the mirex factory, wastewater was generated from the washing process. Mirex was recovered from wastewater before being transferred to the on-site wastewater treatment facility (GEF, 2006). Little mirex was emitted into the environment during the production. (3) Mirex is a kind of highly hydrophobic organic pollutant, which almost only exists in the soil. A negligible percent of mirex can dissolve in the water and volatilize into the air. It is rather difficult for mirex to transport in the ‘‘immobile” soil environment. Therefore, it is reasonable to calculate the general mirex pollution levels according to the consumption, regardless of the industrial activities and production. But for the adjacent area around the factory, special attention should be paid to the higher contamination levels. Then, the model was used to calculate the mirex pollution for other Chinese provinces where mirex has been used for termite

100 – 200 (2) 50 – 100 (3) 20 – 50 (2) 5 – 20 (5) 0.1 – 5 (2) 0 – 0.1 (19)

Fig. 4. General mirex pollution in China: (A) mirex pollution in Chinese provinces and (B) mirex pollution in soil (pg g1 dw).

control. Each province was treated as a separate region. The mirex levels (Fig. 4) and the amounts of mirex in different environmental compartments (Table 2) in Chinese provinces were calculated. The mirex levels were estimated to be relatively higher in the provinces in the southeast of China, where termite damage is serious and the mirex consumption is larger (Fig. 4). The highest concentration occurred in Jiangxi Province, which also had the largest mirex consumption. On a regional scale, the calculated mirex concentrations are generally so low that it seems to pose no harm to human and organisms. Usually, pesticide pollution is significantly related to the point source due to the usage in some local sites. However, such more polluted sites cannot be reflected by the compartment model. The results from the model are just rough estimates of mirex pollution. More field environmental survey and monitoring should be done to fill the data gap. The total amount of mirex in the environment in China was estimated to be about 25.12 tons (Table 2). Most of the mirex existes in soil, accounting for more than 95% of the total amount of mirex. Therefore, the soil should be the priority medium for mirex analysis. In China, the mirex consumption was less than the production. For example, from 1997 to 2001, the total mirex consumption was only 14.1 tons (Table 2), which was even less than the peak annual mirex production in 2000 (31 tons). Therefore, except for the mirex entering various environment matrices via consumption, about 34.2 tons of unused mirex products are still stored in the factories that once produced it (JS EPA, 2007). 4. Conclusions This study determined mirex in soil samples from Liyang using a HRGC/HRMS method. A Level III fugacity model was used to study the general pollution of mirex in China. The mirex levels

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are generally low in China, due to its relatively low production and usage. Generally, the mirex pollution is not a serious problem in China. With the complete forbiddance of the production, use, import and export of mirex in China since May 17, 2009 (MEP et al., 2009), the mirex problem may be a history in the future. However, the risk caused by mirex may still exist at some contaminated point sites for a long period. With the financial support of Global Environmental Facility (GEF), China has planned to perform environmental site assessment on mirex production locations and has recently initiated mirex analysis at some manufacturers (http:// www.china-pops.org). As a preceding study, this study provides general information of mirex pollution in China, and together with the forthcoming mirex analysis data, can help understand better the mirex pollution in China and contribute to the effectiveness evaluation of the implementation of Stockholm Convention. Acknowledgement This work was supported by the Global Environment Research Fund (C-083) of the Ministry of the Environment, Japan. References Bloom, M.S., Vena, J.E., Swanson, M.K., Moysich, K.B., Olson, J.R., 2005. Profiles of ortho-polychlorinated biphenyl congeners, dichlorodiphenyldichloroethylene, hexachlorobenzene, and mirex among male Lake Ontario sportfish consumers: the New York State angler cohort study. Environ. Res. 97, 178–194. Bru, R., Carrasco, J.M., Paraiba, L.C., 1998. Unsteady state fugacity model by a dynamic control system. Appl. Math. Model. 22, 485–494. Chan, H.M., Chan, K.M., Dickman, M., 1999. Organochlorines in Hong Kong fish. Mar. Pollut. Bull. 39, 346–351. Chen, Y.Q., Li, J.S., Wu, X.P., Hu, J., Huang, Y., 2008. Studies on residues of organochloride pesticides (OCPs) in the soils of Xiangjiang river valley. Res. Environ. Sci. 21, 63–67 (in Chinese). Cornish, A.S., Ng, W.C., Ho, V.C.M., Wong, H.L., Lam, J.C.W., Lam, P.K.S., Leung, K.M.Y., 2007. Trace metals and organochlorines in the bamboo shark Chiloscyllium plagiosum from the southern waters of Hong Kong, China. Sci. Total Environ. 376, 335–345. Dai, D., Cao, Y., Falls, G., Levi, P.E., Hodgson, E., Rose, R.L., 2001. Modulation of mouse P450 isoforms CYP1A2, CYP2B10, CYP2E1, and CYP3A by the environmental chemicals mirex, 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene, vinclozolin, and flutamide. Pest. Biochem. Physiol. 70, 127–141. GEF (Global Environment Facility), 2006. China: Demonstration of Alternatives to Chlordane and Mirex in Termite Control Project. Washington, USA. Jallad, K.N., Lynn, B.C., Alley, E.G., 2006. Amine promoted, metal enhanced degradation of Mirex under high temperature conditions. J. Hazard. Mater. 135, 437–442. Jiang, Q.T., Lee, T.K.M., Chen, K., Wong, H.L., Zheng, J.S., Giesy, J.P., Lo, K.K.W., Yamashitad, N., Lam, P.K.S., 2005. Human health risk assessment of organochlorines associated with fish consumption in a coastal city in China. Environ. Pollut. 136, 155–165.

JS EPA (Jiangsu Province Environmental Protection Agency), 2007. Notice of the Control and Surveillance of Mirex Output of Mirex Enterprises. Jiangsu Environmental Notice [2007] No. 2. Kearney, J.P., Cole, D.C., Ferron, L.A., Weber, J.P., 1999. Blood PCB, p,p0 -DDE, and mirex levels in Great Lakes fish and waterfowl consumers in two Ontario communities. Environ. Res. 80, S138–S149. Li, Q.L., Zhu, T., Qiu, X.H., Hu, J.X., Vighi, M., 2006. Evaluating the fate of p,p0 -DDT in Tianjin, China using a non-steady-state multimedia fugacity model. Ecotoxicol. Environ. Saf. 63, 196–203. Mackay, D., 2001. Multimedia Environmental Models: The Fugacity Approach, second ed. Lewis Publishers, Boca Raton. Mackay, D., Paterson, S., 1991. Evaluating the multimedia fate of organic chemicals: a level III fugacity model. Environ. Sci. Technol. 25, 427–436. Mackay, D., Shiu, W.Y., Ma, K.C., Lee, S.C., 2006. Physical–Chemical Properties and Environmental Fate for Organic Chemicals, second ed. CRC Press, Boca Raton. MEP (Ministry of Environmental Protection), NDRC (National Development and Reform Commission), MIIT (Ministry of Industry and Information Technology), MHURD (Ministry of Housing and Urban–Rural Development), MOA (Ministry of Agriculture), MOC (Ministry of Commerce), MOH (Ministry of Health), GAC (General Administration of Customs), GAQSIQ (General Administration of Quality Supervision, Inspection and Quarantine), SAWS (State Administration of Work Safety), 2009. The Forbiddance of Production, Usage, Circulation, Import and Export of DDT, Chlorane, Mirex and HCB. MEP Notice [2009] No. 23. Oh, J.R., Choi, H.K., Hong, S.H., Yim, U.H., Shim, W.J., Kannan, N., 2005. A preliminary report of persistent organochlorine pollutants in the Yellow Sea. Mar. Pollut. Bull. 50, 217–222. Schell, L.M., Gallo, M.V., DeCaprio, A.P., Hubicki, L., Denham, M., Ravenscroft, J., 2004. The Akwesasne Task Force on the Environment. Thyroid function in relation to burden of PCBs, p,p0 -DDE, HCB, mirex and lead among Akwesasne Mohawk youth: a preliminary study. Environ. Toxicol. Pharmacol. 18, 91–99. Shi, S.X., Lu, W.Y., Shao, D.D., Huang, Y.Y., 2008. Studies on residues of organochloride pesticides in soil of tea garden. Chin. J. Soil Sci. 38, 388–392 (in Chinese). UNEP (United Nations Environment Programme), 2001. Stockholm Convention on Persistent Organic Pollutants. Stockholm, Sweden. Wang, B., 2009. Ecological Risk Assessment Model of Persistent Organic Pollutants and its Application. Tsinghua University, Peking [Doctoral dissertation]. Wang, Q., Zhao, N.N., Huang, Q.F., Yi, A.H., Luo, C.Z., 2007. Spatial distribution of chlordane and mirex in typical POPs contaminated site in China. J. AgroEnviron. Sci. 26, 1630–1634 (in Chinese). Wang, W., Batterman, S., Chernyak, S., Nriagu, J., 2008. Concentrations and risks of organic and metal contaminants in Eurasian caviar. Ecotoxicol. Environ. Saf. 71, 138–148. Wang, X.T., 2005. Study of the Toxicity Potential of Pesticide Pops Based on the Long Range Transportation Potential — DDT as a Case. Peking University, Peking [Doctoral dissertation]. Wei, D.B., Kameya, T., Urano, K., 2007. Environmental management of pesticidal POPs in China: past, present and future. Environ. Int. 33, 894–902. Wong, M.H., Leung, A.O.W., Chan, J.K.Y., Choi, M.P.K., 2005. A review on the usage of POP pesticides in China, with emphasis on DDT loadings in human milk. Chemosphere 60, 740–752. Yu, G., Niu, J.F., Huang, J., 2005. Persistent Organic Pollutants—New Global Environmental Problem. Science Press, Beijing.