Development of a retrospective job exposure matrix for PCB-exposed workers in capacitor manufacturing

Polychlorinated biphenyls (PCBs) are considered probable human carcinogens by the International Agency for Research on Cancer and one congener, PCB126, has been rated as a known human carcinogen. A period-specific job exposure matrix (JEM) was developed for former PCB-exposed capacitor manufacturing workers (n=12,605) (1938-1977). A detailed exposure assessment for this plant was based on a number of exposure determinants (proximity, degree of contact with PCBs, temperature, ventilation, process control, job mobility). The intensity and frequency of PCB exposures by job for both inhalation and dermal exposures, and additional chemical exposures were reviewed. The JEM was developed in nine steps: (1) all unique jobs (n=1,684) were assessed using (2) defined PCB exposure determinants; (3) the exposure determinants were used to develop exposure profiles; (4) similar exposure profiles were combined into categories having similar PCB exposures; (5) qualitative intensity (high-medium-low-baseline) and frequency (continuous-intermittent) ratings were developed, and (6) used to qualitatively rate inhalation and dermal exposure separately for each category; (7) quantitative intensity ratings based on available air concentrations were developed for inhalation and dermal exposures based on equal importance of both routes of exposure; (8) adjustments were made for overall exposure, and (9) for each category the product of intensity and frequency was calculated, and exposure in the earlier era was weighted. A period-specific JEM modified for two eras of stable PCB exposure conditions. These exposure estimates, derived from a systematic and rigorous use of the exposure determinant data, lead to cumulative PCB exposure-response relationships in the epidemiological cancer mortality and incidence studies of this cohort

Occupational exposure to acid mists and periodontal attachment loss Exposição ocupacional a névoas ácidas e perda de inserção periodontal

This study investigated the hypotheses that occupational exposure to acid mists is positively associated with periodontal disease, assessed by periodontal attachment loss. The study sample included 530 male workers at a metal processing factory. Data were obtained from interviews and oral examinations. Periodontal attachment loss was defined as > 4mm at probing, in at least one tooth. A job exposure matrix was utilized for exposure evaluation. Exposure to acid mists was positively associated with periodontal attachment loss > 4mm at any time (prevalence ratio, PRadjusted = 2.17), past (PRadjusted = 2.11), and over 6 years of exposure (PRadjusted = 1.77), independently of age, alcohol consumption, and smoking, and these results were limited to workers who did not use dental floss. Exposure to acid mists is a potential risk factor for periodontal attachment loss, and further studies are needed, using longitudinal designs and more accurate exposure measures.<br>Este estudo investigou a hipótese de que a exposição ocupacional a névoas ácidas está associada positivamente à doença periodontal, avaliada através da perda de inserção periodontal. O estudo foi conduzido com 530 trabalhadores do sexo masculino de uma metalúrgica. Os dados foram obtidos por meio de entrevistas individuais e de exames clínicos odontológicos. A perda de inserção periodontal foi avaliada durante a sondagem e definida em > 4mm, em pelo menos um dente. Uma matriz de exposição ocupacional foi utilizada para avaliação da exposição. A exposição a névoas ácidas foi associada positivamente à perda de inserção periodontal > 4mm para a ocorrência da exposição em algum momento (RPajustada = 2,17), exposição passada (RPajustada = 2,11) e duração da exposição maior que seis anos (RPajustada = 1,77), independentemente da idade, consumo de álcool e tabagismo; estes resultados foram observados apenas entre os trabalhadores que não usavam o fio dental. A exposição a névoas ácidas é um fator de risco potencial para a perda de inserção periodontal e são necessários outros estudos que utilizem desenhos longitudinais e medidas de exposição mais acuradas

Exposure profiles of pesticides among greenhouse workers: implications for epidemiological studies.

Contains fulltext : 51497.pdf (publisher's version ) (Closed access)The aim of this study was to assess exposure to pesticides for a longitudinal epidemiological study on adverse reproduction effects among greenhouse workers. Detailed information on pesticide use among greenhouse workers was obtained on a monthly basis through self-administered questionnaires and subsequent workplace surveys. Questionnaires were filled in for a whole year. Dermal exposure rankings were developed for each task using the observational method Dermal Exposure Assessment Method (DREAM). Exposure scores were calculated for each worker for each month during the year, taking into account frequency, duration and exposure intensity for each task. A total number of 116 different active ingredients were used in the population, whereas a mean number of 15 active ingredients were applied per greenhouse. DREAM observations provided insight into the exposure intensity of 12 application techniques and three mixing and loading activities. Relatively high DREAM scores were obtained for scattering, fogging, dusting, and mixing and loading of powders. Observations with DREAM indicated that application with a horizontal ground-boom, motor driven boom, and bulb shower resulted in low dermal exposure. Exposure scores showed substantial variation between workers and over the year. It can be concluded that exposure variation between- and within greenhouses is very large, both in terms of chemical composition and exposure intensity. This may be a significant contributor to the inconsistent results of studies evaluating health effects of pesticide exposure