Human adipose tissue, concentration

Needham et al. (1991) also showed that human adipose tissue concentrations of CDDs may be correlated with blood serum levels after adjusting for total lipid content. On a lipid basis, total CDD/CDFs are higher in blood than adipose tissue. Partitioning is not identical in these tissues 2,3,7,8-TCDD levels are almost identical in blood and adipose tissues, but OCDD levels are higher in blood. However, the presence of OCDD at levels of 5,000-10,000 pg/person when concentrations in food are generally in the low pg/g level suggests that the contribution of food to the OCDD body burden in humans requires further study (Rappe 1993). 

A triaryl phosphate ester, tributoxyethyl phosphate, was detected at a mean concentration of 11.3 ng/g in 41 of 115 human adipose tissue samples taken from cadavers from Kingston and Ottawa, Canada (LeBel and Williams 1986). Because triaryl phosphate esters have been found in Canadian drinking water and... 

Organophosphate Ester Hydraulic Fluids. The measurement of organophosphate esters in fish and human adipose tissue has been used to assess environmental contamination in several studies (Mayer et al. 1981). The methods are able to detect concentrations of 0.1 mg/kg in fish and 2.5 pg/kg in human adipose... 

PCDD/PCDFs accumulate in human adipose tissue, and the level reflects the history of intake by the individual. Several factors have been shown to affect adipose tissue concentrations/body burdens, notably age, the number of children and period of breastfeeding, and dietary habits. Breast-milk represents the most useful matrix for evaluating time trends of dioxins and many other POPs. Several factors affect the PCDD/PCDFs content of human breast-milk, most notably the mothers age, the duration of breast-feeding and the fat content of the milk. Studies should therefore ideally... 

The most recent National Human Adipose Tissue Survey did not detect endrin in adipose tissues from the general U.S. population (Stanley 1986). Endrin also was not detected in adipose breast tissue from breast cancer patients (n=5) or controls (n=5) in the United States (Djordjevic et al. 1994). A 1984 study based on autopsied adipose tissue from 141 cadavers from six Canadian Great Lakes municipalities showed no detectable concentrations of endrin (detection limit 2.4 ppb) (Williams et al. 1988). In a 1990-91 survey, only very low levels of endrin (average concentration 3.27 ng/g (ppb) range 0.23-8.56 ng/g [ppb] lipid)... 

No information was located for the general population on chlordecone concentrations in human adipose tissue or blood as this compound was not included in any major national study (e.g.,... 

In an early report of the 1982 annual results of the National Human Adipose Tissue Survey (NHATS), a compound identified as di- -octylphthalate was reportedly detected in 31% of the composite human adipose tissue samples taken in the various regions of the United States that year. Concentrations in lipid ranged from below the level of detection (9 ng/sample) to a maximum of 850 ng/g (EPA 1986d). However, a later report of the 1982 results stated that the chemical detected was not di- -octylphthalate, but was actually diethylhexyl phthalate (EPA 1989b). 

Exposure Levels in Humans. This information is necessary for assessing the need to conduct health studies on these populations. Di- -oclylphthalatc has historically been reported to have been found in human adipose tissue (EPA 1986d). However, more recent information indicates that the compound detected was actually the branched di(2-ethylhexyl) isomer (EPA 1989b). Additional information on the concentrations of di-n-octylphthalate in human tissues and fluids, particularly for populations living near hazardous waste sites, is needed to assess potential human exposure to the compound. 

A method with LOQ at ppt levels was developed based on LLE followed by GC-AFID for the determination of trace concentrations of nitrobenzene, l-chloro-2-nitrobenzene and synthetic fragrances such as musk xylene (223) and musk ketone (224). The method was applied to study the distribution of these compounds in environmental samples of North Sea waters460. GC with atomic emission detection (AED) has been successfully applied to the determination of nitro musks in human adipose tissues, at ppb concentration levels. A clean-up procedure for nonpolar substances and element-specific detection with AED enabled for the first time target screening analysis for lipophilic nitro aromatic compounds. The lack of sensitivity of AED was compensated by higher concentrations of the extracts... 

Travis CC, Hattemer-Frey HA, Arms AD. 1988. Relationship between dietary intake of organic chemicals and their concentrations in human adipose tissue and breast milk. Arch Environ Contam Toxicol 17 473-478. 

Concentrations (in ng/g Lipid Weight) of Several PBDEs in Human Adipose Tissue Samples... 

Hexabromobiphenyl was detected (detection limit 6.6 g/kg) at a frequency of 8 57% in human adipose tissue samples from six Canadian Great Lakes municipalities in 1984 (Williams et al. 1988). The concentration of 2,2, 4,4, 5,5 -hexabromobiphenyl in adipose tissue samples pooled from tissues of the general population of the conterminous Unites States ranged from 1 to 2 g/kg (Lewis and Sovocool 1982). PBB levels in the adipose tissues of 15 quarantined dairy farm residents in mid-Michigan (where the mix-up involving FireMaster BP-6 occurred) ranged from 0.104 to 174 mg kg (Humphrey and Hayner 1975). 

Liquid dichloromethane is absorbed through human skin, with maximum concentrations in expired air being reached 30 min after exposure (Stewart Dodd, 1964). After 0.5—8 h inhalation exposme, concentrations of dichloromethane in the blood and expired air were directly proportional to dose, over the concentration range 173-1740 mg/ni (DiVincenzo et al., 1972). It is distributed principally to adipose tissue. In male volunteers exposed to 2600 mg/m for 1 h at a work intensity of 50 W, mean adipose tissue concentrations after 1,4 and 22 h were 10.2, 8.4 and 1.7 mg/kg, respectively (Engstrom Bjmstrbm, 1977). Elevated carboxyhaemoglobin saturation and increased urinary formic acid concentrations have been found in exposed workers (Ku elova Vlasak, 1966 DiVincenzo Kaplan, 1981), but inhaled dichloromethane is excreted principally unchanged in expired air (Riley et al, 1966). 

Table9 Residue concentrations of EPCNs (ngg 1 from several countries lipid weight) in human adipose tissue...

Table 2 PBB concentrations in human adipose tissue and serum (in ng/g wet weight), sequenced by decreasing PBB concentration3...

Choi, J.W., Miyabara, Y., Hashimoto, S., Morita, M., 2002. Comparison of PCDD/F and coplanar PCB concentrations in Japanese human adipose tissue collected in 1970-1971, 1994-1996, and 2000. Chemosphere 47, 591-597. 

Geographically, no major differences in the levels of DDT have been reported for human adipose tissues. Based on available data (Table 16.1), the mean concentration of EDDTs in the Asian region is 2.8 pgg-1, and... 

CDD/CDF body burdens, elimination half-lives corrected for alterations in body weight ranged from 3.5 years for 1,2,3,4,6,7,8-HpCDF to 7.9 years for 2,3,7,8-TCDD and 15 years for 1,2,3,4,7,8-HxCDD (Rohde et al. 1997). In the same study, half-lives for elimination due only to fecal excretion ranged from 10 years for OCDD to 22 years for 2,3,7,8-TCDD and 27 years for 1,2,3,7,8-PeCDD. The half-lives for 2,3,4,7,8-PeCDF in humans exposed to contaminated rice oil in the Yusho incident range from 2 to 30 years, and were inversely dependent on adipose tissue concentrations above approximately 10 ng/kg body weight (i.e., the higher the body burden, the faster the elimination) (Ryan et al. 1993a). 

The elimination of 2,3,7,8-TCDD from humans was evaluated using a PBPK model developed by Kissel and Robarge (1988). The steady-state adipose tissue concentration predicted by the model was similar to the lipid-based blood levels reported in the general population with no known special exposure to... 

---