Chlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyl profiles of workers with trichlorophenol and pentachlorophenol exposures
Introduction
Polychlorodibenzo-p-dioxins and polychlorodibenzofurans may be formed as unintended by-products in the production of 2,4,5-trichlorophenol (TCP) and pentachlorophenol (PCP). Studies of persons with significant TCP exposures find 2,3,7,8 tetrachlorodibenzo-p-dioxin (2378-TCDD) levels above background with some of these studies also reporting elevated 12378-PeCDD levels (Nygren et al., 1988, Beck et al., 1989, Papke et al., 1992, Piacitelli et al., 1992, Smith et al., 1992, Ott et al., 1993, Littorin et al., 1994, Flesch-Janys et al., 1996, Heederik et al., 1998, Ryan and Schecter, 2000). Persons exposed to PCP often have 123478-HxCDD, 123678-HxCDD, 123789-HxCDD, 1234678-HpCDD, and OCDD levels above background. Some studies also report higher 12378-PeCDD, 123478-HxCDF, and 1234678-HpCDF levels (Ryan et al., 1987, Papke et al., 1992, Littorin et al., 1994, Schecter et al., 1994, Flesch-Janys et al., 1996, Schecter et al., 1996, Coenraads et al., 1999).
We examined serum dioxin, furan, and PCB levels among former workers in production of TCP and PCP, and compared these levels with workers at the same plant without potential for workplace exposures. These chlorophenol workers have been studied previously in several epidemiology studies (Townsend et al., 1982, Bond et al., 1983, Bond et al., 1989, Bodner et al., 2003). The current study is unusual because workers may have been exposed to either or both TCP and PCP. Thus this study provides a rare opportunity to compare 2,3,7,8-substituted chlorinated dioxins and furans profiles among two types of chlorophenol workers. We will determine if the dioxin and furan profiles for our workers differ from previous studies of TCP and PCP workers, and how distinct the dioxin “fingerprints” are for these chlorophenols many years after workplace exposures have ceased.
Section snippets
Methods
We reported the design and the determinants of the dioxin levels for these workers and the impact of age and body fat on dioxin levels previously (Collins et al., 2006, Collins et al., 2007). In the present study, we now examine the dioxin and furan profiles by occupational exposure source. Briefly, a sample of men living within 50 miles of the Dow Chemical plant in Midland, Michigan who worked at the plant during chlorophenol production was included in the study. These workers had potential
Results
Table 1 presents the lipid adjusted average dioxin, furan, and PCB levels for the four exposed groups and the reference group. Age, body mass index (BMI), the number of months worked at the plant, the number of months with potential for chlorophenol exposures, and the range of last exposure to chlorophenol as also presented. We compare each of the exposed groups to the reference workers. The reference workers averaged 64.0 years of age, had a BMI of 28.8, worked 303.6 months at the plant and
Discussion
We have found distinct “fingerprints” for TCP and PCP workers. TCP workers have mostly increased levels of 2378-TCDD. This finding is consistent with several other studies (Nygren et al., 1988, Beck et al., 1989, Papke et al., 1992, Piacitelli et al., 1992, Smith et al., 1992, Ott et al., 1993, Littorin et al., 1994, Flesch-Janys et al., 1996, Heederik et al., 1998, Ryan and Schecter, 2000). Some studies of persons with TCP exposure do report higher 12378-PeCDD levels. While we do find
Conclusions
In 2004, we examined the serum dioxin levels of 98 long term workers at a plant with chlorophenol units. The years of last exposure to chlorophenol in these units ranged from 1944 to 1980. Even though serum dioxin, furan, and PCB were measured many years after exposure, we found distinct patterns of dioxin congeners among workers with different chlorophenol exposures and we were effectively able to distinguish TCP workers from PCP workers among those with serum dioxin levels above background.
Acknowledgement
This research was funded by The Dow Chemical Company. We would like to thank members of the Dow Chemical’s Health Services staff including Melody Raab, Sandy Murray, Lisa Pressnell, and Kathleen Collins, for arranging the appointments, and drawing and separating the blood, members of the Dow Chemical’s Toxicology Environmental Research Center including Kathy Brzak and Melissa Mielke for storing, packing, and shipping the sera, Tim Bell of Dow Chemical’s Toxicology Environmental Research Center
References (33)
- et al.
Levels of PCDDs and PCDFs in adipose tissue of occupationally exposed workers
Chemosphere
(1989) - et al.
Body mass index and serum chlorinated dibenzo-p-dioxin and dibenzofuran levels
Chemosphere
(2007) - et al.
Body burden levels of dioxin, furans, and PCBs among frequent consumers of Great Lake sport fish
Environ. Res.
(1999) - et al.
Dioxins in blood from Swedish phenoxy herbicide workers
Lancet
(1994) - et al.
Development and validation of a method for determination of PCDDs and PCDFs in human plasma: a multivariate comparison of blood and adipose tissue levels between Viet Nam veterans and matched controls
Chemosphere
(1988) - et al.
Various PCDD/PCDF patterns in human blood resulting from different occupational exposures
Chemosphere
(1992) - et al.
Serum levels of PCDDs and PCDFs among workers exposed to 2,3,7,8-TCDD contaminated chemicals
Chemosphere
(1992) - et al.
Identification of polychlorinated dibenzofurans (PCDFs) in commercial chlorophenol formulations
Chemosphere
(1978) - et al.
Human tissue levels of PCDDs and PCDFs from a fatal pentachlorophenol poisoning
Chemosphere
(1987) - et al.
Comparison of dibenzodioxin levels in blood and milk in agricultural workers and other following pentachlorophenol exposure in China
Chemosphere
(1994)
Exposure to polychlorinated dioxins (PCDD) and dibenzofurans (PCDF) from graphite electrodes in a chloralkali plant
Chemosphere
Cancer risk for chemical workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin
Occup. Environ. Med.
Incidence of chloracne among chemical workers potentially exposed to chlorinated dioxins
J. Occup. Med.
Medical and morbidity surveillance findings among employees potentially exposed to TCDD
Br. J. Ind. Med.
Blood lipid concentrations of dioxin and dibenzofurans causing chloracne
Br. J. Dermatol.
Serum dioxin levels in former chlorophenol workers
J. Exp. Sci. Environ. Epidemiol.
Cited by (12)
Bio-accumulation of organic contaminants in Indo-Pacific humpback dolphins: Preliminary unique features of the brain and testes
2020, Environmental PollutionCitation Excerpt :PCBs are transported into the brain and testes of Indo-Pacific humpback dolphins despite the influence of the blood–brain/testis barrier. Therefore, exposure to PCBs represents a neurotoxicological risk (Collins et al., 2008) and shows negative correlation with circulating reproductive hormone levels in men (Bonde et al., 2008; Goncharov et al., 2009). Exposure to the technical-grade mixture of PCBs such as Aroclor 1254 during development in rats leads to memory and learning disorder (Sable et al., 2006).
Blood levels of dioxins, furans, dioxin-like PCBs, and TEQs in general populations: A review, 1989–2010
2012, Environment InternationalNon-infective occupational risk factors for hepatocellular carcinoma: A review (Review)
2017, Molecular Medicine ReportsHepatocellular carcinoma and the risk of occupational exposure
2016, World Journal of HepatologyExposure data
2016, IARC Monographs on the Evaluation of Carcinogenic Risks to Humans