Associations between blood arsenic and urinary arsenic species concentrations as an exposure characterization tool.

Blood arsenic has various toxicities including carcinogenicity, but urinary concentrations are often substituted to determine the exposure level. Since there is little information on the relation of urinary arsenic species to blood arsenic, the aim was to investigate relationships between blood total arsenic (T-As) and the urinary species adjusted by creatinine and specific gravity (SG). Blood and spot urine samples were collected from 109 Japanese subjects aged 18-66 years without occupational exposure. Positive correlations of blood T-As (median, 3.49 µg/L) with urinary creatinine-adjusted and SG-adjusted T-As and arsenobetaine were statistically significant and greater than those with the unadjusted ones. The magnitude of associations of blood T-As with creatinine-adjusted arsenic species was significantly larger than those with unadjusted or SG-adjusted ones. Most of the correlation coefficients among urinary arsenic species concentrations were significant in three adjustment methods, but there was not a significant correlation between monomethylarsonic acid and arsenobetaine after urinary creatinine and SG corrections. Given multiple regression analysis, plasma T-As concentrations showed significant relations to creatinine-adjusted T-As, dimethylarsinic acid, and arsenobetaine concentrations, but erythrocyte T-As did hardly reflect the variation of urinary arsenic species. In conclusion, creatinine-adjusted arsenic concentrations are suggested to be the most appropriate predictor of blood T-As; by contrast, use of the urinary unadjusted arsenic concentration may result in a misleading interpretation of inorganic arsenic toxicity because the associations between inorganic and organic arsenic species based on the unadjusted concentration were mutually close. Plasma T-As appeared to be the best indicator of low-level exposure in blood samples.

Organochlorine concentrations in breast milk and prevalence of allergic disorders in Japanese women.

Persistent organic pollutants have been shown to have immunomodulating effects in humans. However, epidemiological evidence regarding the relationships between organochlorine compound exposure and allergic disorders coming from studies of children has been limited and inconsistent. The current cross-sectional study examined the associations between the concentrations of ß-hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), p,p'-dichlorodiphenyldichloroethylene (DDE), and trans-nonachlordane in breast milk and the prevalence of allergic disorders in 124 adult Japanese women. The definition of wheeze and asthma was based on criteria from the European Community Respiratory Health Survey whereas that of eczema and rhinoconjunctivitis was based on criteria from the International Study of Asthma and Allergies in Childhood. Adjustment was made for age, smoking, family history of allergic disorders, and education. The prevalence values of wheeze, asthma, eczema, and rhinoconjunctivitis in the past 12 months were 9.7%, 4.8%, 13.7%, and 29.8%, respectively. The median concentrations of ß-HCH, HCB, p,p'-DDE, and trans-nonachlordane in breast milk were 28.3, 7.0, 71.6, and 23.9 ng g(-1) lipid, respectively (range, 4.5-253, 2.1-14.5, 7.5-362, and 1.8-130 ng g(-1) lipid, respectively). When the exposures were treated as continuous variables, no significant associations were found between concentrations of HCB, ß-HCH, p,p'-DDE, or trans-nonachlordane and the prevalence of wheeze, asthma, eczema, or rhinoconjunctivitis. Our results suggest that concentrations of ß-HCH, HCB, p,p'-DDE, and trans-nonachlordane in breast milk are not evidently associated with the prevalence of wheeze, asthma, eczema, or rhinoconjunctivitis in young female Japanese adults.