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S Samuels

Publications and source records attributed to S Samuels.

80 records · Page 5Linked to original sources

Seveso Women's Health Study: does zone of residence predict individual TCDD exposure?

The compound, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), is produced as an unwanted by-product of various chemical reactions and combustion processes, including the manufacture of chlorinated phenols and derivatives. In animals, TCDD exposure is associated with toxic, carcinogenic, developmental, and reproductive effects. In 1976, a chemical plant explosion in Seveso, Italy, exposed the residents in the surrounding community to the highest exposure to TCDD known in humans. Materials from an aerosol cloud of sodium hydroxide, sodium trichlorophenate and TCDD were deposited over an 18.1 km2 area. As evidence of the significant level of TCDD exposure, numerous animals died and 193 cases of chloracne were reported among residents of the area. Initially, the contaminated area was divided into three major exposure Zones (A, B, R) based on the concentration of TCDD in surface soils. To date, the majority of epidemiologic studies conducted in Seveso have used Zone of residence as a proxy measure of exposure. The purpose of the present study is to validate the use of Zone of residence in Seveso as a proxy measure of exposure against individual serum TCDD measurement, and to determine whether questionnaire information can improve the accuracy of the exposure classification. Using data collected from the Seveso Women's Health Study (SWHS), the first comprehensive epidemiologic study of the reproductive health of women in Seveso, we determined that Zone of residence is a good predictor of individual serum TCDD level, explaining 24% of the variance. Using questionnaire information could have improved prediction of individual exposure levels in Seveso, increasing the percent of the variation in serum TCDD levels explained to 42%.

Adolescent↗

Seveso Women's Health Study: a study of the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on reproductive health.

Although reproductive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure have been reported in numerous investigations of animals, studies of this association in humans are limited. In 1976, an explosion in Seveso, Italy exposed the surrounding population to among the highest levels of TCDD recorded in humans. The relatively pure exposure to TCDD and the ability to quantify individual level TCDD exposure from sera collected in 1976 for the Seveso cohort affords a unique opportunity to evaluate the potential dose-response relationship between TCDD exposure and a spectrum of reproductive endpoints. The Seveso Women's Health Study (SWHS) is the first comprehensive study of the reproductive health of a human population exposed to TCDD. The primary objectives of the study are to investigate the relationship of TCDD and the following endpoints: (1) endometriosis; (2) menstrual cycle characteristics; (3) age at menarche; (4) birth outcomes of pregnancies conceived after 1976; (5) time to conception and clinical infertility; and (6) age at menopause. Included in the SWHS cohort are women who were 0-40 yr old in 1976, who have adequate stored sera collected between 1976 and 1980, and who resided in Zones A or B at the time of the accident. All women were interviewed extensively about their reproductive and pregnancy history and had a blood draw. For an eligible subset of women, a pelvic exam and transvaginal ultrasound were conducted and a menstrual diary was completed. More than 95% of the women were located 20 yr after the accident and roughly 80% of the cohort agreed to participate. Data collection was completed in July 1998, serum TCDD analysis of samples for analysis of endometriosis as a nested case-control study was completed in October 1998, and statistical analysis of these data should be completed in early 1999. Serum samples are now being analyzed in order to relate TCDD levels with the remaining reproductive outcomes.

Adult↗

[The relationship between health and job quitting in female workers of the electronics assembly industry in Tijuana].

OBJECTIVE: To examine the health, labor and social factors which contribute to quitting work in two transnational electronic parts factories in Tijuana, Mexico. MATERIAL AND METHODS: A cohort study of 725 women employed either at a Japanese or an American electronic parts factory in Tijuana was performed between January 1992 and March 1994. The sample was stratified in two time intervals < or = 30 or > 30 days of work. Follow up was continued until quitting or end of the observation period, by recollecting data regarding health, social and occupational variables from different logs and reports provided by the employer. Reasons for quitting and accuracy of data obtained from logs and reports were evaluated through a follow up interview applied to 46% (n = 148) of the women who had quit, and were located approximately 12 months after ceasing to work (SD = 6.7). RESULTS: The estimated cumulative probabilities of quitting were 67% during the first year and 81% during the second. Newcomers to the work force, a day shift and the company is nationality were predictors the of quitting within 30 days. Smoking, surgical antecedents and paid leave due to illness were predictors for quitting after 30 days. In contrast, quitting rate after 30 days was lower in women with a history of chronic disease. CONCLUSIONS: Quitting work is high and selective among workers female electronic factories. While occupational factors are associated with workers quitting early, health factors are stronger predictors for quitting after 30 days.

Adult↗