Biomonitoring of a population of Portuguese workers exposed to lead

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Julia Garcia Leston (Author) Other; Joana Roma Torres (Author) Other; Maria Vilares (Author) Other; Rui Pinto (Author) Other; Luis M Cunha (Author) FCUP; Joao Prista (Author) Other; Joao Paulo Teixeira (Author) Other; Olga Mayan (Author) Other; Eduardo Pasaro (Author) Other; Josefina Mendez (Author) Other; Blanca Laffon (Author) Other

Journal

Title: Mutation Research - Genetic Toxicology and Environmental Mutagenesis

Vol. 721 No. 1

Pages: 81-88

ISSN: 1383-5718

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 34 Citations

Scopus - 38 Citations

Scientific classification

FOS: Medical and Health sciences > Basic medicine

Other information

Authenticus ID: P-002-T79

DOI: 10.1016/j.mrgentox.2011.01.001

Abstract (EN): Lead is a heavy metal that has been used for many centuries and it is still used for various industrial purposes thanks to its physical and chemical characteristics. Human exposure to lead can result in a wide range of biological effects depending upon the level and duration of exposure. Despite the fact that lead has been found capable of eliciting genotoxic responses in a wide range of tests, not all studies have been conclusive. Although several experimental studies have shown that lead may modulate immune responses, data in exposed humans are still preliminary. The purpose of our study was to evaluate the genotoxic and immunotoxic effects of lead exposure in a group of 70 male workers from two Portuguese factories. The control group comprised 38 healthy males. The exposed individuals showed significantly higher levels of lead in blood and zinc protoporphyrin, and significantly lower delta-aminolevulinic acid dehydratase activity than the controls, suggesting a relatively high lead exposure. Nevertheless, the limit of 70 mu g/dl for lead in blood established by the Portuguese regulation was never reached. Results of the comet assay were not modified by the exposure, but a significant increase in the mutation frequency in the exposed workers was obtained in the T-cell receptor mutation assay. Furthermore, data obtained in the analysis of the different lymphocyte subsets showed a significant decrease in %CD8(+) cells and a significant increase in the %CD4(+)/%CD8(+) ratio in exposed individuals with regard to the controls. No clear effect was observed for vitamin D receptor genetic polymorphism on the parameters evaluated. In view of our results showing mutagenic and immunotoxic effects related to lead exposure in occupational settings, it seems that the Portuguese biological exposure limit for lead needs to be revised in order to increase the safety of exposed workers.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8