Biological monitoring of carbon disulphide and phthalate exposure in the contemporary rubber industry.
OBJECTIVE
We studied the range in urinary levels of 2-thiothiazolidine-4-carboxyl acid (TTCA), a metabolite of CS2 and phthalic acid (PA), a common metabolite of phthalates, across factories and departments in the contemporary rubber manufacturing industry.


METHODS
Spot urine samples from 101 rubber workers employed in nine different factories were collected on Sunday and during the workweek on Tuesday, Wednesday and Thursday at approximately 4 pm. In total, 386 urine samples were successfully analyzed.


RESULTS
Levels of both biomarkers increased significantly by a factor 2 (paired t-test P-value <0.05) during the working week as compared to the Sunday biomarker levels with absolute increases of approximately 70 microg/l and 5 micromol/mol creatinine for PA and TTCA, respectively. Levels in both biomarkers did not differ markedly between working days. Increases seemed to be restricted to specific factories and/or departments (e.g. molding and curing).


CONCLUSIONS
The results of this study demonstrate that rubber workers in the contemporary rubber industry are exposed to phthalates and low levels of CS2 ( approximately 0.05 ppm) as measured by PA and TTCA, respectively. Exposures to both compounds are largely driven by specific circumstances in factories. Therefore, when estimating exposures to phthalates and CS2 detailed information should be collected on the type and amount of phthalate containing ester plasticizers, dithiocarbamates and thiurams used. Preferably, personal exposure data should be collected. In this case, biological monitoring seems a reasonable approach. However, in the case of PA attention should be given to individual background levels as this could lead to a substantial overestimation of the occupational contribution to total phthalate exposure.
Vermeulen
Roel
R
Division of Cancer Epidemiology and Genetics, Occupational and Environmental Epidemiology Branch, National Cancer Institute, NIH, DHHS, 6120 Executive Boulevard, Rockville, MD 20852, USA. vermeulr@mail.nih.gov
Jönsson
Bo A G
BA
Lindh
Christian H
CH
Kromhout
Hans
H
D000395:Air Pollutants, Occupational / Q000493:pharmacokinetics / Q000633:toxicity*; D002246:Carbon Disulfide / Q000493:pharmacokinetics / Q000633:toxicity*; D004784:Environmental Monitoring; D006207:Half-Life; D006801:Humans; D007221:Industry; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects*; D010795:Phthalic Acids / Q000493:pharmacokinetics / Q000633:toxicity*; D012016:Reference Values; D012408:Rubber; D013844:Thiazoles / Q000652:urine*; D053778:Thiazolidines
D000395:Air Pollutants, Occupational; D010795:Phthalic Acids; D013844:Thiazoles; D053778:Thiazolidines; C031677:2-thioxo-4-thiazolidinecarboxylic acid; C032279:phthalic acid; D012408:Rubber; D002246:Carbon Disulfide