Polychlorinated dibenzo-p-dioxin and dibenzofuran concentrations in serum samples of workers at an infectious waste incineration plant in Japan

In 1998-2000, concentrations of summed polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in the exhaust gas of an infectious waste incineration plant were 17-510 ng toxic equivalents (TEQ)/m(3), which reached levels above the Japanese legal limit value of 80 ng TEQ/m(3). The incinerator ceased operation in November 2000. This study was aimed at determining whether the incinerator workers were exposed to high levels of PCDDs and PCDFs. Blood samples of five workers were collected at 1 month and 16 months after the end of the occupational dioxin exposure. For comparison, blood samples were also collected from control subjects. Ash remaining in the incinerator and dust deposited around the conveyer and incinerator areas were collected; TEQ values were 44 and 10 ng TEQ/g, respectively. A month after the end of occupational dioxin exposure, mean TEQ for the workers was 49.1 pg TEQ/g lipid, which was 2.7 times as high as that for the controls. At 16 months, the mean TEQ for the workers decreased to 29.4 pg TEQ/g lipid, which was 1.6 times that for the controls. Ratios of serum level of each congener of PCDDs and PCDFs between 1 and 16 months after exposure were 0.44 to 0.69. This study showed that the serum dioxin levels for the infectious waste incinerator workers were higher than the controls, and the serum dioxin level decreased after the end of the occupational dioxin exposure.     

Exposure evaluation of dioxins in municipal waste incinerator workers

In Japan, the largest source of dioxin is solid waste incineration plants. Because workers employed at these plants handle fly ash and slag contaminated by dioxins, they can take dioxins into the body during work and their health may be adversely effected. This paper describes the dioxin exposure concentration, daily dioxin intake and blood dioxin level in workers employed at municipal incineration plants. The estimated dioxin exposure concentrations were 0.5 to 7.2 pg TEQ/m3 in the daily operation and 0.2 to 92,000 pg TEQ/m3 in the periodic maintenance. It was also expected that the daily dioxin intake can exceed the tolerable daily intake (TDI) in incineration plants with fly ash of high dioxin concentration. The mean of blood dioxin concentration was 346 pg TEQ/g lipid in the highest exposed worker group of the Toyono-gun incineration plant and those were 11 to 40 pg TEQ/ g lipid in the other incineration plants.     

Health effects of chronic exposure to polychlorinated dibenzo-P-dioxins (PCDD), dibenzofurans (PCDF) and coplanar PCB (Co-PCB) of municipal waste incinerator workers

A national survey of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in emission gases from the municipal waste incinerators in 1997 revealed that the Nose Bika Center was heavily contaminated by PCDF. Ninety-four workers underwent a physical examination, and blood biochemistry, lymphocyte marker, and NK activity studies were carried out, along with blood dioxin measurements. Information on working history, life-style, and dietary habits was obtained by questionnaire and interview. The blood dioxin levels were as follows. The median TEQ of dioxins was 39.7 pg I-TEQ/g lipid, and the range was 13.3 to 805.8. The median 2,3,7,8-TCDD concentration was 3.9 pg TEQ/g lipid, and the range was <1 pg TEQ/g lipid (one case) to 13.4 pg TEQ/g lipid. The median TEQ of coplanar PCB was 10.8 pg I-TEQ/g lipid, and the range was 3.1 to 54.2 pg TEQ/g lipid. The congener-specific distribution was quite similar to that in soil around incinerator and waste in the factory. The relationship between dioxin concentrations and work history in the factory showed that the fluidized incinerator and fly ash treatment areas were high-risk work areas. Correlation analyses between body burden, PCDD/PCDF TEQ, Co-PCB TEQ and various laboratory data showed significant positive correlations between dioxin levels and GGT, total protein, uric acid and calcium, and a negative correlation with Fe. However, these correlations disappeared as a result of multivariate analysis adjusted for age, smoking status, and alcohol drinking. Increased NK activity and lower response to PHA stimulation remained significant even after adjusting for age. History of hyperlipidemia and allergy had significantly increased odds ratios. A study on the risk to other workers in the same type of incinerators is under way. Health effects of chronic exposure mainly to PCDF will be clarified by follow-up.     

Polychlorinated dibenzo-p-dioxin and dibenzofuran concentrations in serum samples of workers at intermittently burning municipal waste incinerators in Japan

Objectives: To find whether or not incinerator workers employed at intermittently burning municipal incineration plants are exposed to high concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs).

Methods: 20 Workers employed at three municipal waste incineration plants (incinerator workers) and 20 controls were studied. The previous job, dietary, smoking, and body weight and height were obtained from a questionnaire survey. Concentrations of PCDDs and PCDFs were measured in serum samples of the workers and the deposited dust of the plants. The influence of occupational exposure on concentrations of PCDDs and PCDFs in serum samples was examined by multiple regression analysis.

Results: Dust analysis showed that dominant constituents were octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) among the PCDDs, and 1,2,3,4,6,7,8-heptachlorodibenzofuran (HpCDF) and octachlorodibenzofuran (OCDF) among the PCDFs. The toxicity equivalents (TEQs) of summed PCDDs and PCDFs in the deposited dust were 0.91, 33, and 11 ng TEQ/g, respectively, for plants I, II, and III. The means of TEQ in serum samples of summed PCDDs and PCDFs in the incinerator workers and controls were 22.8 and 16.4 pg TEQ/g lipid for area I, 29.4 and 19.3 pg TEQ/g lipid for area II, and 22.8 and 24.9 pg TEQ/g lipid for area III, which were almost the same as for the general population of Japan. No significant differences in the TEQ of PCDDs and TEQ of PCDDs and PCDDs were found between the incinerator workers and the controls. However, the TEQ of PCDFs was significantly higher among the incinerator workers in areas I and II, and the 1,2,3,4,6,7,8-HpCDF concentration was also significantly higher for all three areas. When the occupational exposure index for each constituent of PCDDs and PCDFs was defined as the product of the duration of employment at the incineration plant and the concentration of the constituent in the deposited dust, multiple regression analysis showed that the concentrations of HxCDF, HpCDF, and TEQ of PCDFs in serum samples increased with the occupational exposure index. The multiple regression analysis also suggested that significant factors affecting the concentrations in serum samples were area for HxCDD, age for TCDD, PeCDD, PeCDF, TEQ of PCDDs, TEQ of PCDFs, and TEQ of summed PCDDs and PCDFs, and BMI for HxCDD, HpCDD, and OCDD.

Conclusion: This study showed that incinerator workers employed at intermittently burning incineration plants were not necessarily exposed to high concentrations of PCDDs and PCDFs. However, the increases in the concentrations in serum of HxCDF, HpCDF and TEQ of PCDFs with the occupational exposure index suggest that the incinerator workers had inhaled dust containing PCDDs and PCDFs during their work.

     

Health survey on workers and residents near the municipal waste and industrial waste incinerators in Korea

Hazardous substances, such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) also have been detected in Municipal Solid Waste (MSW) and industrial waste incinerators in Korea. In this study, we estimated the exposure status of these hazardous substances and their heath effects in workers and residents near the MSW incinerators and residents near the industrial waste incinerators. We interviewed 13 workers and 16 residents from the area around the two MSW incinerators, and further 10 residents from the area around one industrial waste incinerator, which is suspected to emit higher hazardous substances. During the interview we collected information including sociodemographic information, personal habits, work history, detailed gynecologic and other medical history. Blood samples from 45 subjects were also collected for analysis of PCDDs and PCDFs, which were analyzed by HRGC-HRMS (High Resolution Gas Chromatography-High Resolution Mass Spectrometer). In addition to a questionnaire survey, urinary concentrations of 8-hydroxydeoxyguanosine (8-OH-dG) and malondialdehyde (MDA) were measured as oxidative injury biomarkers. Urinary concentrations of 8-OH-dG were determined by in vitro ELISA (JAICA, Fukuroi, Japan). MDA were determined by HPLC using adduct with TBA (thiobarbituric acid). The PCDD/F concentrations in residents from the area around industrial waste incinerator were higher than those in workers and residents from the area around MSW incinerator. The average toxic equivalency (TEQ) concentrations of PCDD/Fs in residents from the area around industrial waste incinerator were 53.4 pg I-TEQs/g lipid. The average TEQ concentrations of PCDD/Fs in workers and residents near MSW incinerator were 12.2 pg I-TEQs/g lipid. Estimated daily intake (EDI) of each person was calculated, and the EDI of all workers and residents near MSW incinerator were within the tolerable daily intake range. But for only 30% of 10 people near the industrial waste incinerator were the EDI within the tolerable daily intake range (1-4 pg I-TEQ/kg bw/day) suggested by WHO (1997). The oxidative stress of residents near the industrial waste incinerator was higher than that in workers and residents from the area around MSW incinerator. This oxidative stress may have been caused by hazardous substances, such as PCDD/Fs emitted by incinerators. The residents from the area around industrial waste incinerator were exposed to hazardous substances such as PCDD/ Fs. Proper protection strategies against these hazardous chemicals are needed.     

Relationships between dioxin concentrations in deposited dust and those in serum of workers at municipal waste incineration plants]

Relationships between concentrations of polychlorodibenzo-p-dioxins (PCDDs) and polychlorodibenzofurans (PCDFs) in deposited dust and those in the serum of incinerator workers were examined at 13 municipal incineration plants. The following results were found. 1) Dust analysis showed that dominant constituents were octachlorodibenzo-p-dioxin (OCDD) and 1, 2, 3, 4, 6, 7, 8-heptachlorodibenzo-p-dioxin (HpCDD) among PCDDs, and 1, 2, 3, 4, 6, 7, 8-heptachlorodibenzofuran (HpCDF) and octachlorodibenzofuran (OCDF) among PCDFs. The toxicity equivalents (TEQs) of total PCDDs and PCDFs in the deposited dust were 0.54 to 33 ngTEQ/g, which were about 1,000 to 10,000 times as high as those in general soil. 2) The mean of serum TEQ of PCDDs, that of PCDFs and that of total PCDDs and PCDFs in the incinerator workers were 16, 12 and 28 pg TEQ/g lipid, respectively, for all the incinerator workers. Concentrations of hexachlorodibenzofurans (HxCDFs) and HpCDFs in the serum were significantly higher in the incinerator workers than the general population, which suggests that these workers had inhaled these chemicals during their work. 3) The concentration of 1, 2, 3, 4, 6, 7, 8-HpCDF and the TEQ value of PCDFs and in the serum were positively correlated with those in dust except for three plants where large-scale remodeling of the equipment was conducted within the past seven years. Consequently, deposited dust analysis may be useful for judging whether health examination containing blood dioxin measurement is necessary or not.     

Regional Air Pollution Caused by Dioxins from Numerous Emission Sources: Lessons from a Domestic Experience in Japan

In this study, a large-scale field study was performed in order to distinguish between the contribution of the municipal solid waste incinerator and small clustered industrial waste incinerators in Fuchu city. The dioxin concentrations when only the municipal solid waste incinerator was being operated were found to range from 0.047 to 0.090 pg TEQ/m³. The dioxin concentrations when only the clustered small industrial waste incinerators were being operated ranged from 0.085 to 0.25 pg TEQ/m³. The concentrations in ambient air were more strongly affected by the clustered industrial waste incinerators than the municipal solid waste incinerator. Furthermore, the predicted concentrations by an atmospheric dispersion simulation model were consistent with the measured concentrations. From these results, the dioxin concentrations in ambient air were attributed primarily to the clustered small industrial waste incinerators.     

Exposure of maintenance workers to dioxin-like contaminants during the temporary shutdown of a municipal domestic solid waste incinerator: a case series

To evaluate workers' exposure to dioxin-like substances (such as polychlorinated dibenzo-p-dioxins, dibenzofurans, and polychlorinated biphenyls), the authors used a chemical-activated luciferase gene expression (CALUX) assay to determine serum dioxin-like activity in five workers before and after two different cleaning-up activities inside a municipal domestic solid-waste incinerator. The workers' mean serum concentration of dioxin-like substances before the first cleaning operation, shown as a weighted value of toxic equivalents (or TEQs) according to the CALUX test, was 17.2 pg CALUX TEQ/g fat (range = 12-22), which is comparable with concentrations found in similarly aged men in a Flemish environmental health pilot study. After cleaning work, the workers' mean serum concentration was 28.5 pg CALUX TEQ/g fat (range = 18-31). At the second plant stoppage, the workers' mean dioxin-like activity was 15.4 pg CALUX TEQ/g fat (range = 12-21) before and 16.4 pg CALUX TEQ/g fat (range = < 10-32, where 10 pg is the limit of determination) after the cleaning operation. These results indicate that workers may be exposed to dioxin-like substances during their performance of cleaning operations in a municipal domestic solid-waste incinerator.     

Survey on the health effects of chronic exposure to dioxins and its accumulation on workers of a municipal solid waste incinerator,rural part of Osaka Prefecture,and the results of extended survey afterwards

In September 1998 the Ministry of Health and Welfare announced that high concentrations of dioxins were detected in the samples of soil near the incinerator and ash, drainage, sludge and others remained in the furnace and air pollution control devices of municipal solid waste incinerator (MSWI) in rural part of Osaka Prefecture. According to the results the Ministry of Labor immediately organized the "Research and investigation committee on the dioxin problem of Toyono-gun Clean Center" under Japan Industrial Safety and Health Association to investigate the health effects of chronic exposure to dioxins and its accumulation on workers of the incinerator plant. The investigation was carried out in Sept 1998 and from the results, the committee concluded that the concentrations of dioxin among the blood of the workers who had engaged in maintenance of the furnace, the electric dust collector, and the wet scrubber of the incinerator were higher compared with those of residents in surrounding areas. However, there were no signs or findings correlating to blood level of dioxns, and the level was not high enough to induce sufficient health effects from the review of published papers. According to the results of this survey the committee understood that the follow-up study of blood dioxins level of group III and IV workers was inevitable and concerned about the other MSWI workers in Japan who might also be exposed to similar level of dioxins. The Ministry of Labor decided to expand the survey to other MSWI workers in Japan as 3-year project from 1999. The summarized report on the project is appended in this paper.     

Isomer pattern and elimination of dioxins in workers exposed at a municipal waste incineration plant

The aim of this study was to clarify patterns of serum concentrations of dioxins in the employees of a waste incineration plant and to estimate elimination rates and half-lives of serum dioxin isomers, and the maximum serum concentrations of dioxin isomers at the time of plant shutdown. Sixteen subjects participating 3 times or more in annual health examinations during an 8-yr period from 2000 to 2007 were recruited for this study. Serum concentrations of dioxins expressed as TEQ/g lipid decreased gradually after plant shutdown with the highest decrease observed in polychlorinated dibenzofurans (PCDFs) followed by polychlorinated deibenzo-p-dioxins (PCDDs) and then coplanar PCBs. The serum toxic equivalency (TEQ) concentrations of PCDF and PCDD congeners in the employees were higher than those in the general population survey by the Ministry of the Environment, Japan, whereas the serum concentrations of coplanar PCBs were similar to those in the general population. The estimated half-lives and elimination rates of PCDDs and PCDFs in the highly exposed workers increased compared with the moderately exposed workers. The estimated geometric mean serum concentrations of PCDDs, PCDFs and total dioxins at the time of plant shutdown were 35, 53 and 107 pg TEQ/g lipid, respectively.     

Mental health status of municipal solid waste incinerator workers compared with local government office workers

Recently in Japan dioxin problem of municipal solid waste incinerator (MSWI) became social issue. The news spread all around Japan and induced fear that workers at incinerators would suffer from cancer or other serious illness induced by the exposure to dioxins. Authors were interested in the effect of this stressful event occurred to the workers and intended to evaluate mental health status of MSWI workers compared with office workers. Subjects were male workers from two MSWI plants and a local government office; 20 government office workers who were engaging in health administration and 55 MSWI workers. Subjects were interviewed about their age, educational carrier, and working schedule. POMS and GHQ30 were used to evaluate mood status of subjects. There were differences in mood state between the two occupational groups. POMS showed that Tension-Anxiety, Depression-Dejection, and Fatigue levels were high in the health administration worker group. GHQ30 showed that General Illness, Social Dysfunction, and Anxiety and Dysphoria state were deviated to abnormal in the health administration worker group. General mental health status evaluated by GHQ30 score was also deviated to abnormal in the office worker group. Our results showed that mental health status of health administration workers was less healthy compared with MSWI workers. This meant that the stress of MSWI workers enhanced by the fear that they might have been exposed to dioxin did not exceed the stress the health administration workers usually had suffered from.     

Association between dioxins/furans exposures and incinerator workers' hepatic function and blood lipids

This study examined the effects of dioxins/furans on blood lipids and hepatic function and assessed potential interaction between hepatitis B virus (HBV) infection and dioxins on hepatic function for 133 male workers of municipal waste incinerators. We found that total cholesterol levels in workers with blood dioxins/furans levels of 15.4-59.0 pg TEQ/g lipid (high-exposure workers) averaged 13.5 mg/dL higher than workers with 5.5-15.3 pg TEQ/g lipid (low-exposure workers). The adjusted odds ratio for total cholesterol abnormality (>220 mg/dL) was 2.8 (95% confidence interval = 1.0-7.9) between high and low-exposure workers. High-exposure workers showed consistently, although not statistically significantly, higher abnormality in gamma-glutamyltransferase (>52 U/L), alanine aminotransferase (>41 U/L), and aspartate aminotransferase (>37 U/L) than did low-exposure workers. However, there was no statistically significant interaction between dioxins/furans and HBV on these hepatic enzymes among incinerator workers.     

回转窑与立窑水泥生产粉尘危害的对比研究

目的探讨水泥生产中采用的回转窑法和立窑法的粉尘控制效果及其对作业人员健康的危害情况,为今后水泥生产的粉尘控制提供科学依据。方法根据我国《建设项目职业病危害控制效果评价技术导则》等要求,对尘源及其浓度进行调查、检测,根据《职业健康监护技术规范》对接尘工人进行职业健康检查。本次检测是在生产线所有设备运转正常、满负荷生产中进行。选择有代表性的地点、工种进行检测,连续检测3个工作日,每个工作日分上、下午各1次。结果回转窑生产方法对粉尘危害的控制效果显著好于立窑生产方法,两种水泥生产方法主要接尘工种的粉尘合格率分别为86.57%和32.11%;主要尘源点粉尘合格率分别为83.94%和15.62%,两者差异均有统计学意义(χ2=198.2,P<0.05)。回转窑水泥厂体检了4 210名粉尘作业工人,检出尘肺观察对象以上者29人,检出率为0.67%;立窑水泥厂体检了1 300名粉尘作业工人,检出尘肺观察对象以上者65人,检出率为4.23%。两种窑尘肺检出率差异有统计学意义(χ2=8 291.1,P<0.05)。结论回转窑在生产过程中对粉尘的控制效果明显好于立窑,其粉尘对作业人员的危害相对于小立窑,改革水泥生产工艺、提高水泥生产自动化、机械化是降低水泥生产过程粉尘危害的关键。     

Effects of dioxin on metabolism of estrogens in waste incinerator workers

The authors measured the concentrations of serum dioxins and urinary estrogen metabolites in 57 male waste incinerator workers to determine whether dioxin influenced the metabolism of estrogens. Concentrations of serum dioxin levels and urinary estrogen metabolites, such as estrone, 17beta-estradiol, 2-hydroxyestrone, 2-methoxyestrone, 2-hydroxyestradiol, 2-methoxyestradiol, 4-hydroxyestrone, 4-hydroxyestradiol, 4-methoxyestradiol, 16-hydroxyestrone, and estriol from the workers were measured. An analysis of covariance showed that mean estriol concentrations, adjusted for confounding factors among 3 serum dioxin levels, indicated a progressive increase with increasing serum dioxin level: 1.30, 1.41, and 2.02 nmol/mol creatinine at < 30.3, 30.3-39.7, and > 39.7 pg toxicity equivalent quantity/g lipid, respectively (F = 3.56, p = .036). This study showed that dioxin acts to metabolize estrogens to 16-hydroxyestrogens rather than to 2- or 4-hydroxyestrogens.     

某固废拆解基地母乳中多氯联苯含量及其婴儿的暴露风险

目的通过测定某固废拆解基地妇女乳汁中多氯联苯(PCBs)的浓度,了解该地区母体的负荷水平和类二英PCBs分布情况,并且对婴儿通过母乳摄入多氯联苯的风险进行评估。方法在拆解区和对照区分别采集20和12份母乳,用气相色谱测定母乳中总PCBs(t-PCBs)的浓度,并对两地区各一份混合母乳样进行类二英PCBs检测。结果拆解区和对照区母乳中t-PCBs浓度为0·39~3·92μg/g脂肪和0~0·46μg/g脂肪(只检测出1例)。拆解区和对照区PCBs总TEQ值分别为59pg/gfat和6pg/gfat。结论拆解区妇女乳汁中t-PCBs高于大多数国家和地区的水平,其婴儿每日通过母乳类二英摄入量远远大于WHO推荐的成人每日耐受量。     

Worker exposure to organic vapors at a liquid chemical waste incinerator

The extent of employee exposure to organic vapors at a liquid/fluid chemical waste incinerator facility was assessed by means of a preliminary survey. The study was conducted at a facility owned by the Metropolitan Sewer District of Greater Cincinnati, Cincinnati, OH. The incineration unit employs a rotary kiln and a cyclone furnace (liquid injection) with a common combustion chamber. A wide variety of liquid industrial chemical wastes are accepted in tank truck quantities. Low flow air pumps were used to collect breathing zone and general area samples on standard 150-mg charcoal tubes. The samples were analyzed by a gas chromatograph equipped with a flame ionization detector. Benzene, methyl ethyl ketone (MEK), toluene and xylene, solvents common to many of the wastes accepted, were selected for determination. The data indicate that the routine operation of this liquid industrial waste incinerator facility results in worker exposure considerably less than the action level (50% of the health standard) for all compounds tested, except benzene. Some workers were at risk of overexposure to benzene if the NIOSH-recommended criteria are used, but not when the OSHA and ACGIH criteria are used. The highest exposure routine operations were cleaning pump strainers after receiving wastes and benzene distillations conducted in the laboratory. The non-routine operation of storage tank entry, which occurred once during the study, resulted in the highest potential exposure of any operation.     

Attic dust and human blood samples collected near a former wood treatment facility

A wood treatment facility operating in southern Alabama released dioxins and other hazardous substances into the surrounding community over a period of approximately 35 years. The facility used a variety of chemical insecticides including pentachlorophenol (PCP), chromated copper arsenate (CCA), and creosote (which contains polycyclic aromatic hydrocarbons (PAHs)) to treat wood. The health risks associated with the released contaminants are numerous and significant. To evaluate the historic exposure to the contaminants from the facility, blood samples and health surveys were collected from 21 current and past residents of the adjacent, isolated community and analyzed for concentrations of polychlorinated dibenzo-p-dioxins (dioxins) and polychlorinated dibenzofurans (furans). In addition, attic dust sampling was performed in 11 buildings located within a 1-mile radius of the former wood treatment facility. The average total dioxin toxic equivalent (TEQ) concentration in the residents' blood samples was 36.6 pg/g lipids. In the attic dust, the average total dioxin TEQ concentration, benzo[a]pyrene (PAH) TEQ concentration, and arsenic concentration were 145 ng/kg, 0.98 and 29.8 mg/kg, respectively. The concentrations of dioxins measured in the blood samples exceed the 90th percentile total dioxin levels found in the general US adult population. Concentrations of dioxin, arsenic, and PAHs found in the attic samples exceeded the US Environmental Protection Agency (USEPA) Region 4 soil exposure cancer risk preliminary remediation goal (PRG) values. These findings indicate a very significant potential for related health effects in these communities.     

Dioxin concentrations in the blood of workers at municipal waste incinerators.

OBJECTIVES--Increased concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) in pooled blood samples from workers at municipal waste incinerators have been reported. This study was undertaken to confirm these results in individual blood samples from potentially exposed and unexposed workers at municipal waste incinerators compared with matched unexposed controls and compared with concentrations in the slag and fly ash from the municipal waste incinerators. METHODS--Concentrations of PCDDs and PCDFs were determined in the blood of 10 workers from an old municipal waste incinerator without adequate pollution controls, 11 workers from a newer incinerator with modern pollution controls, and 25 controls from the general population group matched for age (+/- 10 years), sex, and race, and in the slag and fly ash from the older incinerator. RESULTS--Significant increases of certain PCDDs and PCDFs were found in the blood of the workers from the older incinerator compared with the controls as follows: octaCDD (1051 (438) v 637 (344), P < 0.001), hexaCDF (52.3 (28.7) v 30.2 (18.2), P < 0.01), heptaCDF (43.9 (30.4) v 22.7 (12.4), P < 0.001), total PCDDs (1262 (484) v 825 (454), P < 0.001), total PCDFs (133.0 (68.1) v 93.7 (36.7), P < 0.05), and total PCDD/Fs (1395 (537) v 918 (437), P < 0.001). The workers from the older incinerator with the greatest exposure were found to have the most significant increases of the blood PCDDs and PCDFs, and the pattern of increased PCDD and PCDF congeners in the blood corresponded to the pattern in the incinerator slag and ash. No significant differences were found between the blood concentrations of the workers at the newer incinerator and the controls. CONCLUSION--Occupational exposure to slag and fly ash from municipal waste incinerators may increase the blood concentrations of PCDDs and PCDFs. Modern pollution control technology in new incinerators may be able to minimise potential exposure to slag and fly ash and thus the absorption of PCDDs and PCDFs from this source.     

Polychlorinated dioxins,furans, and biphenyls in blood of children and adults living in a dioxin-contaminated area in Tokyo

The soil of a residential area in Tokyo was found to contain dioxins, namely polychlorinated dioxins, furans, and dioxin-like biphenyls, the levels of which exceeded the environmental guideline [1,000 pg toxic equivalent (TEQ)/g] by up to 6.8 times. To assess the exposure levels of people living in this area and to study the possible relationship of blood dioxin concentrations of children with breast milk and/or formula feeding, a health survey was carried out in 2006, involving a total of 138 people, including 66 children aged 3–15 years, and blood dioxin concentrations and the characteristics and lifestyles of these people were analyzed. Mean ± standard error of the mean (SEM) of blood dioxin concentrations (pg/g-lipid) of group 1 (3–6 years old), group 2 (7–15 years old), and group 3 (≥16 years old) were 13 ± 1.9, 6.6 ± 0.65, and 10 ± 0.54, respectively. The congener/isomer profile of dioxins in blood samples differed markedly from that of the contaminated soil samples. According to the feeding mode of children, blood dioxin concentrations (pg/g-lipid) were 17 ± 2.9 for breast milk only, 7.4 ± 0.82 for both breast milk and formula, and 4.7 ± 1.1 for formula only, with a significant difference from one another. We conclude that people living in the dioxin-contaminated area are less likely to be exposed to excessive amounts of dioxins, and that blood dioxin concentrations of children aged 3–15 years seem to be strongly affected by breast feeding duration.     

Negative association between serum dioxin level and oxidative DNA damage markers in municipal waste incinerator workers

Objectives: To investigate the effect of dioxin on the formation of oxidative DNA damage and urinary mutagenicity, we measured the concentrations of serum dioxins and lymphocytic 8-hydroxydeoxyguanosine (8-OH-dG) in 57 male waste incinerator workers, urinary 8-OH-dG and urinary mutagenicity in 29 male waste incinerator workers. Methods: Information about the subjects was obtained from a questionnaire. Concentrations of polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), and coplanar-polychlorinated-biphenyl (Co-PCB) in serum samples from the workers were measured with a high-resolution gas chromatograph /high-resolution mass spectrometer. Lymphocytic and urinary 8-OH-dG levels were measured with a high-performance liquid chromatography-electrochemical detector system. The urinary mutagenicity was measured with umu assay. Results: The lymphocytic 8-OH-dG level showed a negative association with the serum dioxin level (total value of TEQ-PCDD, PCDF, and Co-PCB). Urinary 8-OH-dG did not show correlation with serum dioxin level, but showed positive correlation with the smoking index. Conclusions: With respect to the subjects‘ serum dioxin level, dioxin did not increase the urinary 8-OH-dG level by oxidative DNA damage, but upregulation of the primary defenses with oxidative damage and/or DNA repair system activity might have occurred.