Rita de Cássia Oliveira da Costa Mattos

Influência de fatores socioeconômicos na contaminaçäo por agrotóxicos, Brasil

OBJETIVO: A elevada utilizacao de agrotoxicos, sem os cuidados necessarios, tem contribuido para a degradacao ambiental e o aumento das intoxicacoes ocupacionais, sendo um dos principais problemas de saude publica no meio rural brasileiro. O objetivo do trabalho e avaliar a exposicao de um grupo de trabalhadores da area rural do Estado do Rio de Janeiro a agrotoxicos anticolinesterasicos, atraves das atividades da acetilcolinesterase eritrocitaria (AChE) e da butirilcolinesterase plasmatica (BChE), e o impacto de alguns indicadores socioeconomicos e de utilizacao de agrotoxicos sobre a contaminacao humana. METODOS: Para a avaliacao da exposicao de 300 agricultores residentes em cinco comunidades do distrito de Mage, RJ, uma amostra aleatoria de 55 trabalhadores foi selecionada e determinadas as atividades individuais de acetilcolinesterase eritrocitartia (AChE) e butirilcolinesterase plasmatica (BChE). As atividades enzimaticas foram avaliadas segundo o metodo de Ellman modificado por Oliveira-Silva. Dados socioeconomicos e de utilizacao de agrotoxicos para cada trabalhador da amostra foram obtidos em entrevista estruturada. O possivel papel dos indicadores socioeconomicos e de uso de agrotoxicos sobre o nivel de contaminacao dos trabalhadores foi estimado por analise de regressao linear multipla, utilizando-se a atividade enzimatica como variavel dependente e os indicadores socioeconomicos e de uso de agrotoxicos como variaveis independentes. RESULTADOS E CONCLUSOES: Os dados obtidos mostraram resultados distintos em relacao a incidencia da exposicao excessiva, de acordo com o indicador enzimatico utilizado. No grupo de trabalhadores, 3,6% (2) foram identificados pelos resultados de BChE e 41,8% (23) pela AChE, sendo considerados intoxicados individuos com pelo menos um dos indicadores positivos. A avaliacao desses dados frente aos indicadores socioeconomicos e de utilizacao de agrotoxicos, destaca a importância do nivel de escolaridade sobre a prevalencia das intoxicacoes. Para os demais determinantes estudados, nenhuma correlacao significativa foi tao evidente.

Avaliação dos fatores de risco relacionados à exposição ao chumbo em crianças e adolescentes do Rio de Janeiro

The importance of atmospheric lead in environmental global contamination is receiving increasing scientific attention. The main exposure monitoring approach is biological, but the environmental one has a key role, since the environment is the major source of exposure. The study aimed to identify the contamination sources and potential risk factors of the exposure in a 64 subject group formed by 0-16 years-old children from an economically deprived community in Rio de Janeiro. Lead concentrations in soil, water, dust and air were determined and neurological and carcinogenic risk factors for ingestion and inhalation were calculated. Blood samples were collected and used in the analysis of Pb-B, ALA-D% and ALA-D genotyping. The observed neurological risk factor was 549 times higher than reference dose for dust and 554 times higher in the case of ingestion. The carcinogenic risk factor for ingestion was about 4 times. Mean Pb-B was 5.6μg/dL and 40% of the children presented Pb-B levels above the 6μg/dL cutoff value. Mean ALA-D% was 40.3% and a correlation between Pb-B and ALA-D% was observed. ALAD1-2 genotype was identified in 10% of the children. The results will allow the understanding of our reality, supporting public health and environment organizations to carry out control actions and all-encompassing environmental surveillance.

Uso da poeira e do ar como indicadores de contaminação ambiental em áreas circunvizinhas a uma fonte de emissão estacionária de chumbo

This study measured lead concentrations in both the outdoor air and household dust from houses located around a lead-acid battery repair shop. Such installations are one of the largest sources of lead exposure, since outdated technology is still used, coupled with the lack of strict air-quality control programs. Measurements of the air lead concentration around the repair shop were carried out at 6 points, approximately 25 and 500 m from the shop. Over 50% of the air samples exceeded the limit of 1.5 microg Pb.m-3 (range 0.03 - 183.3 microg Pb.m-3). House dust samples were collected from 6 places in houses located at approximately 25, 50, and 500 m from the repair shop, and the concentration of 1,500 microg Pb.m-2 for lead in house dust was exceeded in 44% of the samples, with results varying from 2.2 to 54,338.9 microg Pb.m-2.

The Role of Chemical Interactions Between Thorium, Cerium, and Lanthanum in Lymphocyte Toxicity

ABSTRACT. Thorium, cerium, and lanthanum are metals present in several types of minerals, the most common of which is monazite. Cerium and lanthanum are elements in the lanthanides series. Thorium, an actinide metal, is a hazardous element due to its radioactive characteristics. There is a lack of information describing the possible chemical interactions among these elements and the effects they may have on humans. Toxicological analyses were performed using cell viability, cell death, and DNA damage assays. Chemical interactions were evaluated based on the Loewe additivity model. The results indicate that thorium and cerium individually have no toxic effects on lymphocytes. However, thorium associated with lanthanum increases the toxicity of this element, thereby reducing the viability of lymphocytes at low concentrations of metals in the mixture.

Effects of sub-lethal and chronic lead concentrations on blood and liver ALA-D activity and hematological parameters in Nile tilapia

Liver and blood δ-aminolevulinic acid dehydratase (ALA-D) inhibition by exposure to sub-lethal lead concentrations over time in Nile tilapia (Oreochromis niloticus) were investigated. All three lead concentrations (1mgkg(-1), 10mgkg(-1) and 100mgkg(-1)) significantly inhibited ALA-D activity in blood (319±29.2; 180±14.6 and 172±19µmols(-1)h(-1)L(-1) respectively) and liver (302±5.84; 201±41.4 and 93±22.1µmols(-1)h(-1)L(-1)) 24h after injection relative to controls (blood: 597±37.0µmols(-1)h(-1)L(-1); liver: 376±23.1µmols(-1)h(-1)L(-1)). Blood ALA-D was greatly inhibited in all but the highest lead dose. Fish were then exposed to 1mgkg(-1) lead for 9 days, and presented short-term hyperglycemia, decreased hemoglobin and hematocrit values and time-dependent blood ALA-D activity inhibition, corroborating blood ALA-D activity as being more suitable for investigating lead effects, showing dose and time-dependent ALA-D inhibition after lead exposure. The results of the present study also demonstrated that fish size affects blood ALA-D activity, as fish from the 24-h assay, which were slightly smaller (approximately 200g), showed higher ALA-D inhibition in response to lead exposure when compared to the fish from the 9-day assay (approximately 500g). Thus, fish size should always be taken into account both in the field and in laboratory settings, and efforts should be made to obtain uniform fish size samples for biomarker studies.

Limites de aplicabilidade da determinação do ácido delta-aminolevulínico urinário como teste screening na avaliação da intoxicação profissional pelo chumbo

The relationship between concentrations of ALA-U and Pb-S for two groups of workers is reported. The first group consisted of workers from a telephone company, and the second, of workers from battery factories with average Pb-S equivalent to 17.3 (g/dl (6.2-39.4) and 61.5 (g/dl (41.1-91.0), respectively. The aim of this study was to evaluate the utilization of ALA-U levels as a screening test for different levels of lead in blood by means of High Performance Liquid Chromatography (HPLC) and of spectrophotometry. A significant correlation was found between measured ALA and levels of blood lead (R = 0.739 - first group; R = 0.902 - second group; p < 0.001). The validity of ALA-U test to evaluate different levels of lead in blood was also studied. By using ALA levels of 3mg/g creatinine as a threshold to detect levels of lead in blood equal to or higher than 20 (g/dl, the test results, for the workers in the first group, showed sensibility of 92% and specificity of 90%. In both groups, the false positives as well the false negatives were lower than 10% which was enough to validate the test.The relationship between concentrations of ALA-U and Pb-S for two groups of workers is reported. The first group consisted of workers from a telephone company, and the second, of workers from battery factories with average Pb-S equivalent to 17,3 µg/dl (6,2-39,4) and 61,5 µg/dl (41,1-91,0), respectively. The aim of this study was to evaluate the utilization of ALA-U levels as a screening test for different levels of lead in blood by means of High Performance Liquid Chromatography (HPLC) and of spectrophotometry. A significant correlation was found between measured ALA and levels of blood lead (R = 0,739 - first group; R = 0,902 - second group; p < 0,001). The validity of ALA-U test to evaluate different levels of lead in blood was also studied. By using ALA levels of 3 mg/g creatinine as a threshold to detect levels of lead in blood equal to or higher than 20 µg/dl, the test results, for the workers in the first group, showed sensitivity of 92% and specificity of 90%. In both groups, the false positives as well as the false negatives were lower than 10%, which was enough to validate the test.

Avaliação da poluição ambiental causada por particulado de chumbo emitido por uma reformadora de baterias na cidade do Rio de Janeiro, Brasil

In this study, the lead (Pb) levels in the air surrounding a battery repair shop were measured before and after installation of an exhaust system. Samples were collected in six and four points located at approximately 25 m and 500 m, respectively, from the battery repair shop. The limit of 1.5mg Pb.m-3 air was exceeded in 50% of the samples, ranging from 0.07 to 183.3mg Pb.m-3. After changes in the battery repair shops interior layout and use of the exhaust system, three points were selected, corresponding to the highest concentrations found previously. The new levels ranged from 0.8 to 17.6mg Pb.m-3, demonstrating a significant decrease in the lead content discharged into the environment after meeting the exhaust requirements.

Controle das emissões de chumbo particulado no entorno de uma reformadora de baterias da cidade do Rio de Janeiro usando ar como indicador

Lead levels in the air surrounding a battery repair shop (BRS) located in the Olaria neighborhood (Rio de Janeiro, Brazil) were monitored from April to July 1999. Most of the samples collected within 25 meters of the BRS exceeded the limit of 1.5µg.Pb.m-3 established by the United States Environmental Protection Agency (EPA). These results were published in a previous article (Quiterio et al., 2001). In the current study, installation of a Venture ventilation system and some changes in the operational procedure were proposed. After the modifications in the BRS, a new monitoring campaign was performed (August and September, 2000). Three points were selected for air collection, corresponding to the most critical points found in the previous assessments. The new concentrations ranged from 0.8 to 17.6µg.Pb.m-3, showing that lead emissions into the environment had decreased adequately. However, concentration at the chimney exhaust was still higher than EPA limits, and further improvements in the installations and procedures are definitely needed.No periodo entre abril a julho de 1999, foram realizadas determinacoes dos niveis de chumbo no ar ambiente nas proximidades de uma reformadora de baterias (RB) situada em Olaria (Rio de Janeiro, Brasil). A maioria das amostras coletadas a uma distância de ate 25m da RB excederam o limite de 1,5µg.Pb.m-3 estabelecido pela Environmental Protect Agency (EPA), Estados Unidos. Esses resultados ja foram publicados previamente (Quiterio et al., 2001). Neste trabalho, foram propostas a instalacao de um sistema de exaustao Venture e algumas mudancas nos procedimentos operacionais. Apos as modificacoes na RB, foi realizada uma nova campanha de monitoramento (agosto e setembro de 2000). As coletas foram realizadas nos tres pontos considerados mais criticos, segundo as determinacoes anteriores. As concentracoes medidas estiveram no intervalo 0,8-17,6µg.Pb.m-3, mostrando que as emissoes de chumbo na atmosfera tiveram uma diminuicao adequada. Contudo, a concentracao na saida da chamine e ainda maior que os limites estabelecidos pela EPA e, certamente, serao necessarias outras melhorias nas instalacoes e procedimentos.

Evaluation of calcium excretion in Brazilian infantile and young population environmentally exposed to lead.

Lead exposure is an important issue in the research of several toxic effects resulting from the biochemical interaction between this metal and the organism. Calcium is a fundamental mineral for the maintenance of the organism homeostasis where there is interaction between lead and calcium in metabolic pathways. Environmental lead exposure by verifying the usefulness and applicability of urinary calcium/creatinine ratio (UCa/Cr) in this context was evaluated. This was an extensive socio-demographic study of the nutritional profile, lead exposure biomarkers in blood and the urine and UCa/Cr ratio. The children studied were from a low socio-economic group characterized by unsatisfactory nutritional diet. Lead environmental exposure was shown by biomarkers, with UCa/Cr ratio having positive and significant correlations with both lead and δ-aminolevulinic acid in urine (ALA-U), without colinearity diagnosis. There was a strong association between calcium excretion and lead exposure as a result of linear regression construction models. In children, lead increases calcium excretion which is an additional risk to infantile health. Urinary calcium/creatinine ratio may be a useful tool in the biological monitoring of lead exposure and health promotion programs.

Ototoxicity of hydrocarbons present in gasoline: a literature review

Mailing Address: Thaís Fernandes da Silva CESTEH/ENSP/FIOCRUZ Rua Galileu, 154 Cachambi CEP: 20785-070 Rio de Janeiro, Rio de Janeiro, Brasil E-mail: tsilvafe@gmail.com ABSTRACT Purpose: to investigate the toxicity effects of major hydrocarbons present in gasoline on the auditory system and the related mechanisms of action. Methods: a literature review between 2005 and 2015 was conducted using LILACS, MEDLINE and SciELO, by combining descriptors and their respective terms in Portuguese, English and Spanish. Results: studies performed in humans and animals with hearing impairment, confirmed by morphological tests in rats, the influence of factors such as dose, duration, species and type of stimulus in hearing loss, and ineffective protection of workers by the threshold levels of exposure in the mixture of the compounds, were chosen. Conclusion: toluene is regarded as an ototoxic compound that damages outer hair cells in the middle region of the cochlea, with evidence of interaction with noise. Ethylbenzene and xylenes can be considered potentially ototoxic based on the results of animal studies. No sufficient data were found on benzene to form a conclusion.