137
Toxic Evaluation of Chlorinated Aromatic Environments
Hydrocarbons
in Human
Yoshito Masuda Daiichi College of Pharmaceutical Sciences
Fukuoka, Japan 1.
Introduction
been used in various industrial materials such as are wasted, PCBs remain without decomposing in the environment and accumulate in animal tissue through the food chain (Tatsukawa, 1976). Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are originated from the contamination in chemicals and the thermal reactions of chlorinated compounds, for example from the incineration of municipal and industrial waste (Masuda, 1988). The PCDDs and PCDFs also contaminate the environment and animal tissue. PCBs, PCDDs, and PCDFs consist of 209, 75, and 135 isomers, respectively, by the number of chlorine atoms and the position of chlorine. Some of the PCB, PCDD, and PCDF isomers are very toxic to animals and the toxicity is variable depending on the animal species (Hansen, 1987; Nishizumi, 1987). The toxicities of individual isomers have been evaluated from numerous toxicological experiments on various animals, and their relative toxicities compared to most toxic 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD); TCDD toxic equivalent factors, have been considered by various organizations in the world (Bellin & Barns, 1987; Kutz et al., 1988). The total toxicities of environmental samples polluted with PCDDs and PCDFs have been assessed by the TCDD toxic equivalents obtained from the concentrations of PCDD and PCDF isomers and the TCDD toxic equivalent factors. Yusho, a mass food poisoning, occurred in Western Japan in 1968 because of ingestion of rice oil contaminated with PCBs, PCDFs, PCDDs, and many other chlorinated aromatics (Kuratsune, 1980). Some of the Yusho patients were examined for their intake of the rice oil and clinical symptoms. Therefore, the human toxicities of PCBs, PCDFs, and PCDDs can be elucidated from these data. The human toxicity will be important to evaluate the toxicities of environmental samples polluted with PCBs, PCDFs, and PCDDs. Toxicities of environmental samples have been evaluated by the concentrations of PCDDs and PCDFs. Most of the environmental samples however are polluted not only with PCDDs and PCDFs but also with PCBs at relatively high concentrations (Jensen, 1987). The toxicities of coplanar PCBs are estimated to be comparable to some of the toxic PCDDs and PCDFs (Sawyer & Safe, 1982). Therefore, toxicities of coplanar PCBs should be taken into consideration in evaluating the environmental samples for toxicities of PCDDs and PCDFs.
Polychlorinated biphenyls (PCBs) have
transformers, capacitors, paints, and non-carbon copying paper. When they
’
2.
Evaluation of environmental pollution
by TCDD equivalents
’
.
,
Many American and European countries have adopted the acceptable daily intakes (ADI) pg/kg/day for controlling the level of PCDDs and PCDFs in the environment (WHO, 1987). Japan has not set the ADI but has used the Evaluating Indicator, 100 pg/kg/day, for assessing municipal incinerators (Suzuki et al., 1984). When the quantities of ADI or Evaluating Indicafrom 1 to 10
assumed to be contained in air, water, fish, and breast milk, concentrations of TCDD toxic 1. Concentrations of PCDDs and PCDFs in air of Kobe were measured as 8, 6, and 8.8 pg/M3 (Nakano et al., 1987), calculating < 0.4 pg/m3 of TCDD equivalent. Flue gas from a municipal incinerator is assumed to be dispersed 200,000 times when it reached to the ground surface where people live. Therefore, the concentrations 800 to 80,000 ng/m3 of TCDD equivalent in flue gas are considered to be allowable under the ADI 1 to 100 pg/kg/day (Table 1). The concentration of PCDDs and PCDFs were determined less than 24,000 ng/m3 in Japanese incinerators (Hiraoka et al., 1987a), calculating less than 480 ng/m3 for TCDD equivalent. No data have been reported for PCDDs and PCDFs in drinking water in Japan. Water tor are
equivalent are estimated as listed in Table
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
138 from the landfill of fly ash from municipal incinerator was determined for PCDDs and PCDFs at 15.9 ng/L (Hiraoka et al., 1987b), estimating probably to 0.32 ppt of TCDD equivalent. Fish in American and European countries were frequently analyzed for PCDDs and PCDFs and their TCDD equivalents were calculated. However, only a few data have been reported in Japan (Miyata et al., 1987). The data suggests that TCDD equivalents in Japanese fish and shellfish are calculated to be 10 ppt at the highest. Japanese may ingest 6 pg/kg/day level of TCDD equivalent with fish in an extreme case. Japanese breast milk (Ogaki et al., 1987) was calculated to contain 35 ppt (fat basis) of TCDD equivalent on average. Japanese babies probably ingest more than 100 pg/kg/day level of TCDD equivalent with breast milk during lactation. TABLE 1
&dquo;
,
.
Calculated concentration of TCDD equivalent in air, water, and food, the ADI values of TCDD contaminate them.
assuming
’
3.
Environmental risk evaluation
by Yusho poisoning
The ADI values used for assessment of environmental levels of PCDDs and PCDFs were estimated from the toxicity in animals. Human toxicity of PCDDs and PCDFs is important for elucidating the ADI values. Yusho, a mass food poisoning caused by rice oil containing PCBs, PCDFs, PCDDs, and other chlorinated aromatics, occurred in Western Japan in 1968. Intakes of PCBs, PCDFs, and clinical symptoms were examined in some group of Yusho patients (Hayabuchi et al., 1979). Table 2 lists the intakes of rice oil and TCDD equivalent calculated from concentrations of PCDF and PCDD isomers in the rice oil (Tanabe et al., 1989). The smallest daily intake of TCDD equivalent, 28 ng/kg/day was obtained from a patient who had consumed 0.0311 ml/kg/day of rice oil for 135 days of latent period. Intake of 100 pg/kg/day, 1/280 of 28 ng/kg/day, for several years would not cause any Yusho like symptoms. Normal people in Japan are assumed to consume TCDD equivalent less than 100 pg/kg/day by air, water, and fish. However, some babies seem to consume TCDD equivalent of more than 100 pg/kg/day for several months of lactat-
ing period. 4.
Environmental levels of PCBs, PCDDs, and PCDFs
’
Environmental samples are contaminated with not only PCDDs and PCDFs but also PCBs and their PCB levels are usually much higher than those of PCDDs and PCDFs (Jensen, 1987). Asthe toxicities of most PCBs are much weaker than those of PCDDs and PCDFs, toxicological
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
139
TABLE 2 Estimated intakes of rice oil and TCDD
equivalent
in Yusho
patients
TCDD equivalents are calculated by 0.905 ppm in Yusho oil. Cited from Hayabuchi et al., ( 1979).
TABLE 3 Concentrations and TCDD
for major components of human adipose tissue
equivalents
PCDDs, PCDFs and PCBs in
* Relative potencies are calculated from AHH data of Safe. Cited from Kannan et al. (1988).
contributions of environmental samples have been considered with only toxic PCDDs and PCDFs. However, coplanar PCBs are much toxic than other PCBs and the toxicity of 3,4,5,3’,4’-pentachlorodiphenyl is comparable to those of toxic PCDDs (Sawyer & Safe, 1982; Safe, 1986). Coplanar PCBs are minor components in the PCBs of environmental pollution. However, their concentrations are much higher than those of PCDDs and PCDFs in most of polluted sample in the environment (Tanabe et al., 1987). For that example, Table 3 shows the concentrations of toxic
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
140
PCDDs, PCDFs and PCBs in human adipose tissue (Kannan
et al., 1988). The TCDD toxic PCDDs and PCDFs from the international method the toxic are cited factors used for equivalent (Kutz et al., 1988). The relative potencies for coplanar PCBs are obtained from the aromatic hydrocarbon hydroxylase activities relative to that of TCDD. The concentration of TCDD equivalents were calculated from the concentrations and equivalent factors. Toxic contribution of the PCBs (72.5%) is higher than those of PCDDs and PCDFs in the human adipose tissue (Table 3). As the environmental animals have been reported to be contaminated with coplanar PCBs much higher than PCDDs and PCDFs, their toxic threat will be mainly by coplanar PCBs and minor by PCDDs and PCDFs. Coplanar PCBs are significant compounds of toxic importance in the environmental animals.
References
’
’
BELLIN, J.S. and BARNS, D.G. (1987). "Interim procedure for estimating risks associated with exposure to mixtures of chlorinated dibenzo-p-dioxins and dibenzofurans (CDDs and CDFs)." Risk Assessment Forum, U.S. Environmental Protection Agency, 1.27. HANSEN, L.G. (1987). "Environmental toxicology of polychlorinated biphenyls." In: Environmental Toxin Series 1 (S. Safe and O. Hutzinger, eds.) Springer-Verlag, Berlin. pp. 16-48. HAYABUCHI, H., YOSHIMURA, T., and KURATSUNE, M. (1979). "Consumption of toxic rice oil by ’Yusho’ patients and its relation to the clinical response and latent period." Food Cosmet. Toxicol. 17: 445-461.
HIRAOKA, M., TAKIZAWA, Y., MASUDA, Y., TAKESHITA, R., YAGOME, K., TANAKA, M., WATANABE, Y., and MORIKAWA, K. (1987a). "Investigation on generation of dioxins and related
1901-1906. compounds from municipal incinerators in Japan." Chemosphere 16:
HIRAOKA, M., TAKIZAWA, Y., MASUDA, Y., TAKESHITA, R., TANAKA, M., YAGOME, K., and WATANABE, Y. (1987b). "Study on the Mechanism of Generations of Dioxins and Related
Compounds
in
Disposal of Waste
Materials."
Ministry of Health
and
Welfare, Tokyo. pp.7-65. JENSEN, A.A. (1987). "Polychlorobiphenyls (PCBs), polychlorodibenzo-p-dioxins (PCDDs) and polychlorodibenzofurans (PCDFs) in human milk, blood and adipose tissue." Science Total Environ. 64: 259-293.
KANNAN, N., TANABE, S., and TATSUKAWA, R. (1988). "Potentially hazardous residues of non-ortho substituted 14.
11coplanar PCBs in human adipose tissue." Arch. Environ. Health 43:
KURATSUNE, M. (1980). "Yusho." In: Halogenated Biphenyls, Terphenyls, Naphthalens, Dibenzodioxins and Related Products (R.D. Biomedical Press, Amsterdam. pp.287-302.
Kimbrough, ed.) Elsevier/North-Holand
KUTZ, F.W., BOTTIMORE, D.P., BRETTHAUER, E.W., and MCNELIS, D.N. (1988). "History and achievements of the NATO/CCMS pilot study on international information
exchange on dioxins." Chemosphere 17,
11:N2-7.
MASUDA, Y. (1988). "Environmental pollution of polychlorinated dibenzo-p-dioxins and dibenzofurans." Eisei Kagaku 34: 197-209.
MIYATA, H., TAKAYAMA, K., OGAKI, J., and KASHIMOTO, T. (1987). "Monitoring of PCDDs in Osaka
1817-1822. bay using blue mussel." Chemosphere 16:
NAKANO, T., TSUJI, M., and OKUNO, T. (1987). "Level of chlorinated organic compounds in the
atmosphere." Chemosphere
16:1781-1786.
10 : NISHIZUMI, M. (1987). "Toxicity of dioxins in laboratory animals." Toxicology Forum 575582.
OGAKI, J., TAKAYAMA, K., MIYATA, H., and KASHIMOTO, T. (1987). "Levels of PCDDs and PCDFs in human tissues and various foodstuffs in
Japan." Chemosphere
2047-2056. 16:
SAFE, S.H. (1986). "Comparative toxicology and mechanism of action of polychlorinated
dibenzo-p-dioxins and dibenzofurans." Ann. Rev. Pharmacol.
371-399. Toxicol. 26:
SAWYER, T. and SAFE, S. (1982). "PCB isomers and congeners: Induction of aryl hydrocarbon
hydroxylase and Lett. 87-94. 13:
ethoxyresorfin O-deethylase enzyme activities in rat hepatoma cells." Toxicol.
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
141
SUZUKI, T., GODA, T., TAKESHITA, R., TATSUKAWA, R., TANAKA, M., HIRAYAMA, N., MASUDA, Y., and YAMAGUCHI, S. (19840. "Problems on Dioxins Concerning
Disposal of Waste Materials." Ministry of Health and Welfare, Toyko. pp.1-16. TANABE, S., KANNAN, N., SABRAMANIAN, AN., WATANABE, S., AND TATSUKAWA, R. (1987). "High toxic coplanar PCBs: Occurrence, source, persistency and toxic
147-163. implications to wildlife and human." Environ. Pollut. 47:
TANABE, S., KANNAN, N., OKAMOTO, T., WAKIMOTO, T., TATSUKAWA, R., and MASUDA, Y. (1989). "Isomer-specific determination and toxic evaluation of potentially hazardous coplanar PCBs, dibenzo-furans and dioxins in the tissues of ’Yusho’ PCB poisoning victim and in the causal oil." Toxicol Environ. Chem. (In press). TATSUKAWA, R. (1976). "PCB pollution of Japanese environment." In: PCB Poisoning and Pollution (K. Higuchi, ed.) Kodansha Ltd. and Academic Press, Toyko. pp.147-179. WORLD HEALTH ORGANIZATION (WHO). (1987). IPCS Environmental Health Criteria chlorinated Dibenzo-para-dioxins and Dibenzofurans. WHO, Geneva. pp.1-339.
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
Poly-
Toxic Evaluation of Chlorinated Aromatic Environments
Hydrocarbons
in Human
Yoshito Masuda Daiichi College of Pharmaceutical Sciences
Fukuoka, Japan 1.
Introduction
been used in various industrial materials such as are wasted, PCBs remain without decomposing in the environment and accumulate in animal tissue through the food chain (Tatsukawa, 1976). Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are originated from the contamination in chemicals and the thermal reactions of chlorinated compounds, for example from the incineration of municipal and industrial waste (Masuda, 1988). The PCDDs and PCDFs also contaminate the environment and animal tissue. PCBs, PCDDs, and PCDFs consist of 209, 75, and 135 isomers, respectively, by the number of chlorine atoms and the position of chlorine. Some of the PCB, PCDD, and PCDF isomers are very toxic to animals and the toxicity is variable depending on the animal species (Hansen, 1987; Nishizumi, 1987). The toxicities of individual isomers have been evaluated from numerous toxicological experiments on various animals, and their relative toxicities compared to most toxic 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD); TCDD toxic equivalent factors, have been considered by various organizations in the world (Bellin & Barns, 1987; Kutz et al., 1988). The total toxicities of environmental samples polluted with PCDDs and PCDFs have been assessed by the TCDD toxic equivalents obtained from the concentrations of PCDD and PCDF isomers and the TCDD toxic equivalent factors. Yusho, a mass food poisoning, occurred in Western Japan in 1968 because of ingestion of rice oil contaminated with PCBs, PCDFs, PCDDs, and many other chlorinated aromatics (Kuratsune, 1980). Some of the Yusho patients were examined for their intake of the rice oil and clinical symptoms. Therefore, the human toxicities of PCBs, PCDFs, and PCDDs can be elucidated from these data. The human toxicity will be important to evaluate the toxicities of environmental samples polluted with PCBs, PCDFs, and PCDDs. Toxicities of environmental samples have been evaluated by the concentrations of PCDDs and PCDFs. Most of the environmental samples however are polluted not only with PCDDs and PCDFs but also with PCBs at relatively high concentrations (Jensen, 1987). The toxicities of coplanar PCBs are estimated to be comparable to some of the toxic PCDDs and PCDFs (Sawyer & Safe, 1982). Therefore, toxicities of coplanar PCBs should be taken into consideration in evaluating the environmental samples for toxicities of PCDDs and PCDFs.
Polychlorinated biphenyls (PCBs) have
transformers, capacitors, paints, and non-carbon copying paper. When they
’
2.
Evaluation of environmental pollution
by TCDD equivalents
’
.
,
Many American and European countries have adopted the acceptable daily intakes (ADI) pg/kg/day for controlling the level of PCDDs and PCDFs in the environment (WHO, 1987). Japan has not set the ADI but has used the Evaluating Indicator, 100 pg/kg/day, for assessing municipal incinerators (Suzuki et al., 1984). When the quantities of ADI or Evaluating Indicafrom 1 to 10
assumed to be contained in air, water, fish, and breast milk, concentrations of TCDD toxic 1. Concentrations of PCDDs and PCDFs in air of Kobe were measured as 8, 6, and 8.8 pg/M3 (Nakano et al., 1987), calculating < 0.4 pg/m3 of TCDD equivalent. Flue gas from a municipal incinerator is assumed to be dispersed 200,000 times when it reached to the ground surface where people live. Therefore, the concentrations 800 to 80,000 ng/m3 of TCDD equivalent in flue gas are considered to be allowable under the ADI 1 to 100 pg/kg/day (Table 1). The concentration of PCDDs and PCDFs were determined less than 24,000 ng/m3 in Japanese incinerators (Hiraoka et al., 1987a), calculating less than 480 ng/m3 for TCDD equivalent. No data have been reported for PCDDs and PCDFs in drinking water in Japan. Water tor are
equivalent are estimated as listed in Table
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
138 from the landfill of fly ash from municipal incinerator was determined for PCDDs and PCDFs at 15.9 ng/L (Hiraoka et al., 1987b), estimating probably to 0.32 ppt of TCDD equivalent. Fish in American and European countries were frequently analyzed for PCDDs and PCDFs and their TCDD equivalents were calculated. However, only a few data have been reported in Japan (Miyata et al., 1987). The data suggests that TCDD equivalents in Japanese fish and shellfish are calculated to be 10 ppt at the highest. Japanese may ingest 6 pg/kg/day level of TCDD equivalent with fish in an extreme case. Japanese breast milk (Ogaki et al., 1987) was calculated to contain 35 ppt (fat basis) of TCDD equivalent on average. Japanese babies probably ingest more than 100 pg/kg/day level of TCDD equivalent with breast milk during lactation. TABLE 1
&dquo;
,
.
Calculated concentration of TCDD equivalent in air, water, and food, the ADI values of TCDD contaminate them.
assuming
’
3.
Environmental risk evaluation
by Yusho poisoning
The ADI values used for assessment of environmental levels of PCDDs and PCDFs were estimated from the toxicity in animals. Human toxicity of PCDDs and PCDFs is important for elucidating the ADI values. Yusho, a mass food poisoning caused by rice oil containing PCBs, PCDFs, PCDDs, and other chlorinated aromatics, occurred in Western Japan in 1968. Intakes of PCBs, PCDFs, and clinical symptoms were examined in some group of Yusho patients (Hayabuchi et al., 1979). Table 2 lists the intakes of rice oil and TCDD equivalent calculated from concentrations of PCDF and PCDD isomers in the rice oil (Tanabe et al., 1989). The smallest daily intake of TCDD equivalent, 28 ng/kg/day was obtained from a patient who had consumed 0.0311 ml/kg/day of rice oil for 135 days of latent period. Intake of 100 pg/kg/day, 1/280 of 28 ng/kg/day, for several years would not cause any Yusho like symptoms. Normal people in Japan are assumed to consume TCDD equivalent less than 100 pg/kg/day by air, water, and fish. However, some babies seem to consume TCDD equivalent of more than 100 pg/kg/day for several months of lactat-
ing period. 4.
Environmental levels of PCBs, PCDDs, and PCDFs
’
Environmental samples are contaminated with not only PCDDs and PCDFs but also PCBs and their PCB levels are usually much higher than those of PCDDs and PCDFs (Jensen, 1987). Asthe toxicities of most PCBs are much weaker than those of PCDDs and PCDFs, toxicological
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
139
TABLE 2 Estimated intakes of rice oil and TCDD
equivalent
in Yusho
patients
TCDD equivalents are calculated by 0.905 ppm in Yusho oil. Cited from Hayabuchi et al., ( 1979).
TABLE 3 Concentrations and TCDD
for major components of human adipose tissue
equivalents
PCDDs, PCDFs and PCBs in
* Relative potencies are calculated from AHH data of Safe. Cited from Kannan et al. (1988).
contributions of environmental samples have been considered with only toxic PCDDs and PCDFs. However, coplanar PCBs are much toxic than other PCBs and the toxicity of 3,4,5,3’,4’-pentachlorodiphenyl is comparable to those of toxic PCDDs (Sawyer & Safe, 1982; Safe, 1986). Coplanar PCBs are minor components in the PCBs of environmental pollution. However, their concentrations are much higher than those of PCDDs and PCDFs in most of polluted sample in the environment (Tanabe et al., 1987). For that example, Table 3 shows the concentrations of toxic
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
140
PCDDs, PCDFs and PCBs in human adipose tissue (Kannan
et al., 1988). The TCDD toxic PCDDs and PCDFs from the international method the toxic are cited factors used for equivalent (Kutz et al., 1988). The relative potencies for coplanar PCBs are obtained from the aromatic hydrocarbon hydroxylase activities relative to that of TCDD. The concentration of TCDD equivalents were calculated from the concentrations and equivalent factors. Toxic contribution of the PCBs (72.5%) is higher than those of PCDDs and PCDFs in the human adipose tissue (Table 3). As the environmental animals have been reported to be contaminated with coplanar PCBs much higher than PCDDs and PCDFs, their toxic threat will be mainly by coplanar PCBs and minor by PCDDs and PCDFs. Coplanar PCBs are significant compounds of toxic importance in the environmental animals.
References
’
’
BELLIN, J.S. and BARNS, D.G. (1987). "Interim procedure for estimating risks associated with exposure to mixtures of chlorinated dibenzo-p-dioxins and dibenzofurans (CDDs and CDFs)." Risk Assessment Forum, U.S. Environmental Protection Agency, 1.27. HANSEN, L.G. (1987). "Environmental toxicology of polychlorinated biphenyls." In: Environmental Toxin Series 1 (S. Safe and O. Hutzinger, eds.) Springer-Verlag, Berlin. pp. 16-48. HAYABUCHI, H., YOSHIMURA, T., and KURATSUNE, M. (1979). "Consumption of toxic rice oil by ’Yusho’ patients and its relation to the clinical response and latent period." Food Cosmet. Toxicol. 17: 445-461.
HIRAOKA, M., TAKIZAWA, Y., MASUDA, Y., TAKESHITA, R., YAGOME, K., TANAKA, M., WATANABE, Y., and MORIKAWA, K. (1987a). "Investigation on generation of dioxins and related
1901-1906. compounds from municipal incinerators in Japan." Chemosphere 16:
HIRAOKA, M., TAKIZAWA, Y., MASUDA, Y., TAKESHITA, R., TANAKA, M., YAGOME, K., and WATANABE, Y. (1987b). "Study on the Mechanism of Generations of Dioxins and Related
Compounds
in
Disposal of Waste
Materials."
Ministry of Health
and
Welfare, Tokyo. pp.7-65. JENSEN, A.A. (1987). "Polychlorobiphenyls (PCBs), polychlorodibenzo-p-dioxins (PCDDs) and polychlorodibenzofurans (PCDFs) in human milk, blood and adipose tissue." Science Total Environ. 64: 259-293.
KANNAN, N., TANABE, S., and TATSUKAWA, R. (1988). "Potentially hazardous residues of non-ortho substituted 14.
11coplanar PCBs in human adipose tissue." Arch. Environ. Health 43:
KURATSUNE, M. (1980). "Yusho." In: Halogenated Biphenyls, Terphenyls, Naphthalens, Dibenzodioxins and Related Products (R.D. Biomedical Press, Amsterdam. pp.287-302.
Kimbrough, ed.) Elsevier/North-Holand
KUTZ, F.W., BOTTIMORE, D.P., BRETTHAUER, E.W., and MCNELIS, D.N. (1988). "History and achievements of the NATO/CCMS pilot study on international information
exchange on dioxins." Chemosphere 17,
11:N2-7.
MASUDA, Y. (1988). "Environmental pollution of polychlorinated dibenzo-p-dioxins and dibenzofurans." Eisei Kagaku 34: 197-209.
MIYATA, H., TAKAYAMA, K., OGAKI, J., and KASHIMOTO, T. (1987). "Monitoring of PCDDs in Osaka
1817-1822. bay using blue mussel." Chemosphere 16:
NAKANO, T., TSUJI, M., and OKUNO, T. (1987). "Level of chlorinated organic compounds in the
atmosphere." Chemosphere
16:1781-1786.
10 : NISHIZUMI, M. (1987). "Toxicity of dioxins in laboratory animals." Toxicology Forum 575582.
OGAKI, J., TAKAYAMA, K., MIYATA, H., and KASHIMOTO, T. (1987). "Levels of PCDDs and PCDFs in human tissues and various foodstuffs in
Japan." Chemosphere
2047-2056. 16:
SAFE, S.H. (1986). "Comparative toxicology and mechanism of action of polychlorinated
dibenzo-p-dioxins and dibenzofurans." Ann. Rev. Pharmacol.
371-399. Toxicol. 26:
SAWYER, T. and SAFE, S. (1982). "PCB isomers and congeners: Induction of aryl hydrocarbon
hydroxylase and Lett. 87-94. 13:
ethoxyresorfin O-deethylase enzyme activities in rat hepatoma cells." Toxicol.
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
141
SUZUKI, T., GODA, T., TAKESHITA, R., TATSUKAWA, R., TANAKA, M., HIRAYAMA, N., MASUDA, Y., and YAMAGUCHI, S. (19840. "Problems on Dioxins Concerning
Disposal of Waste Materials." Ministry of Health and Welfare, Toyko. pp.1-16. TANABE, S., KANNAN, N., SABRAMANIAN, AN., WATANABE, S., AND TATSUKAWA, R. (1987). "High toxic coplanar PCBs: Occurrence, source, persistency and toxic
147-163. implications to wildlife and human." Environ. Pollut. 47:
TANABE, S., KANNAN, N., OKAMOTO, T., WAKIMOTO, T., TATSUKAWA, R., and MASUDA, Y. (1989). "Isomer-specific determination and toxic evaluation of potentially hazardous coplanar PCBs, dibenzo-furans and dioxins in the tissues of ’Yusho’ PCB poisoning victim and in the causal oil." Toxicol Environ. Chem. (In press). TATSUKAWA, R. (1976). "PCB pollution of Japanese environment." In: PCB Poisoning and Pollution (K. Higuchi, ed.) Kodansha Ltd. and Academic Press, Toyko. pp.147-179. WORLD HEALTH ORGANIZATION (WHO). (1987). IPCS Environmental Health Criteria chlorinated Dibenzo-para-dioxins and Dibenzofurans. WHO, Geneva. pp.1-339.
Downloaded from tih.sagepub.com at CARLETON UNIV on June 16, 2015
Poly-
