Assessment of occupational exposure of dental professionals to mercury in dental offices of a public primary health care in Maringá, Paraná State, Brazil

Abstract

ABSTRACT. In order to evaluate the occupational exposure of dental professionals to metallic mercury in dental offices of a public primary health care in the city of Maringá, Brazil, samples of blood and urine were collected from 149 dental professionals (group exposed), and 51 healthy adults similar for age and gender of the exposed group (control group) in September and October, 2008. Urinary mercury was determined using atomic absorption spectrophotometry, urea and creatinine in blood and urine by UV/VIS spectrophotometry and analysis of physical, chemical and microbiological characteristics of the urine by reactive bands. The program 'Statistic' version 7.1 and the software R version 2.6.2 were used for the statistical calculations. Urinary mercury was 2.08 ± 2.11 μg g -1 creatinine in workers exposed to mercury and 0.36 ± 0.62 μg g -1 creatinine in the control group (p < 0.05). Urinary levels of mercury were below the maximum allowed by the biological index established in Brazil (35 μg g -1 creatinine); 11% of these professionals (n = 16) had mercury levels above the reference value (5.0 μg g -1 creatinine), whereas the maximum value found was 13 μg g -1 creatinine. The dental professionals of public primary health care in the city of Maringa was exposed to metallic mercury at levels 5.8 times higher than the non-exposed subjects.Keywords: mercury poisoning, health evaluation, occupational exposure, odontology, biomonitoring.Avaliação da exposição ocupacional de profissionais de odontologia ao mercúrio em unidades básicas de saúde de Maringá, Estado do Paraná, Brasil RESUMO. Para avaliar a exposição ocupacional dos profissionais de odontologia ao mercúrio metálico nas Unidades Básicas de Saúde (UBS) de Maringá, Brasil, foram coletadas amostras de sangue e urina de 149 profissionais de odontologia (grupo exposto) e de 51 adultos saudáveis similares em relação à idade e ao gênero do grupo exposto (grupo controle), no período de setembro e outubro de 2008. Foi determinado o mercúrio urinário por espectrofotometria de absorção atômica, a uréia e creatinina no sangue por espectrofotometria UV/VIS, e análise dos aspectos físicos, químicos e microbiológicos da urina por fitas reativas. Para a análise estatística foi utilizado o programa Statistic versão 7.1 e o R versão 2.6.2. O mercúrio urinário foi 2,08 ± 2,11 μg g Palavras-chave: intoxicação por mercúrio, avaliação da saúde, exposição ocupacional, odontologia, biomonitoramento.

<b>Impact of exposure to low levels of mercury on the health of dental workers

“…The dentists and assistants worked 20 and 30 hours a week, respectively. Concerning the time as professionals, the average was 17 ± 7 years for the dentists and 14 ± 8 years for assistants (Oliveira, Nishiyama, Gasparetto, & Machinski Júnior, 2012). Unlike our study, the groups were younger and the assistants worked 10 hours less per week, but they had more time in the profession.…”

“…The average Hg-U of exposed group in Maringá, Paraná State, Brazil (Oliveira et al, 2012), was 2.08 ± 2.11 μg g -1 creatinine (2.97 ± 3.01 μg L -1 ) while the controls was 0.36 ± 0.62 μg g -1 (0.51 ± 0.89 μg L -1 ), level over five times that in the last group and higher than that found among the exposed in Rio de Janeiro.…”