Catecholamine contents of different region of adult rat brain are altered following short and long-term exposures to Pb[+2]

Catecholamine is a group of neurotransmitters that is believed to be responsible for the normal function of animal brain. Physiological and behavioral changes of human body have been reported due to the damage of the brain function following lead exposure. Due to the assumption of lead disposal in brain tissue with two year for its half-life, which results in alteration of brain function, we investigated the ability of lead to change the brain catecholamines during short and long-term studies. Rats were exposed daily with varying amounts of lead and catecholamine contents of cerebellum, mid-brain and brain cortex were determined. Acute peritoneal administration of single dose of lead as lead acetate [260 micro mol/Kg] after 2 h reduced [p < 0.05] the catecholamine levels of cerebellum, mid-brain and cortex part by 34.9%, 35.44% and 23.8%, respectively. The extension of experiment time to 5 h, significant [p < 0.05] reductions in catecholamine levels of mentioned regions of brain by 32.35%, 12.35% and 19.3% were seen respectively. Daily intraperitoneal administration of 10 micro mol/Kg lead for 30 and 60 days reduced catecholamines levels of cerebellum [22.22% and 30.44%], midbrain [12.48% and 26.27%] and brain cortex [11.58% and 26.7%] respectively. It might be concluded that brain dysfunction in lead intoxicated rat occurred through the reduction in the catecholamine levels of different parts of brain. Lead might be therefore considered as a probable factor in causing neurological disease in lead exposed man

Chumbo, ambiente e saúde: o desafio do controle da exposição humana / Lead, environment and health: the challenge of controlling human exposure

Esta publicação reúne estudos abrangentes sobre as fontes e distribuição do chumbo no ambiente, desafios ao controle da exposição humana, e resultados das investigações realizadas nas principais áreas contaminadas por chumbo no Brasil. Reúne textos de pesquisadores do Brasil, Uruguai e Portugal, abordando também aspectos sobre efeitos do chumbo no organismo humano, como danos ao sistema nervoso central e outros agravos à saúde

El estres oxidativo como mecanismo de accion del plomo. Implicancias terapeuticas / Oxidative stress as a mechanism of action of lead. Therapeutic implications

El plomo (Pb) es un metal no esencial altamente toxico que afecta a diversos organos y tejidos. Si bien aun no ha sido descripto un mecanismo unico mediante el cual este metal ejerce sus efectos toxicos, un gran numero de estudios han puesto en evidencia el rol fundamental del estres oxidativo en la intoxicacion por Pb. A este respecto, ha sido informado que en la intoxicaci¨®n por Pb el estres oxidativo puede ocurrir a diferentes niveles: por generacion de acido ¦Ã-aminolevulinico (¦Ã-ALA), por la capacidad per se que posee el Pb para inducir peroxidacion lipidica en presencia de ion ferroso (Fe2+), o por deplecion de glutati¨®n (GSH) y enzimas antioxidantes. Sobre la base de estos antecedentes, el objetivo de esta revision es presentar evidencias recientes sobre la implicancia del estres oxidativo en los efectos adversos ocasionados por Pb, destacar la posibilidad de utilizacion de biomarcadores de estres oxidativo como un metodo complementario al diagnostico temprano de exposicion y revelar la importancia de los compuestos antioxidantes como nuevas herramientas en la prevencion y tratamiento de la intoxicacion por este metal.

Lead (Pb) is a highly toxic non-essential metal that affects different organs and tissues. Although at the present a unique mechanism by which this metal exerts its toxic effects has not been described, a large number of studies have highlighted the fundamental role of oxidative stress in the pathophysiology of Pb poisoning. In this regard, it has been reported that Pb-induced oxidative stress can occur at different levels: by the generation of ¦Ã-aminolevulinic acid (¦Ã-ALA), through its ability to induce lipid peroxidation in the presence of ferrous ion (Fe2+), or via glutathione (GSH) or antioxidant enzyme depletion. On the basis of these antecedents, the aim of this review is to present recent evidence regarding the implication of oxidative stress in the adverse effects caused by Pb, to emphasize the possibility to use oxidative stress biomarkers as a complementary method for early detection of Pb exposure, and to reveal the importance of antioxidant compounds as novel tools in the prevention and treatment of Pb exposure.

Diseño y aplicación de un Programa de Comunicación de Riesgos para la salud ambiental infantil en un sitio contaminado con plomo y arsénico / Designing and application of a Risk Communication Program for children environmental health on a lead and arsenic contaminated location

Una industria metalúrgica en la ciudad de San Luis Potosí, México ha contaminado el sitio con plomo (Pb) y arsénico (As) principalmente. Desde 1989 se han reportado por nuestro grupo altas concentraciones de Pb en sangre (PbS) y As en orina (AsO) en los niños del lugar. En el presente estudio se generó un Programa de Comunicación Riesgos (PCR) para informar a los niños sobre los riesgos ambientales del sitio donde viven y que cambiaran conductas para disminuir la exposición al Pb y al As. Se trabajó con 170 niños (5 a 7 años) de la zona. Se aplicó el PCR y se realizó la evaluación mediante análisis de dibujos, cuestionarios y monitoreo biológico. En los dibujos de los niños se encontraron elementos tóxicos tales como el Pb, la tierra contaminada, entre otros. En los cuestionarios aplicados a los niños y a los padres de familia se pudo apreciar un cambio en los conocimientos y en algunas conductas respecto a los contaminantes, sus efectos y su exposición. No se encontró una disminución en los niveles de PbS ni de AsO. Esto quizás porque la principal ruta de exposición no es únicamente el suelo, como se había contemplado anteriormente.

A metallurgical industry in San Luis Potosí city, México, has contaminated the zone by lead (Pb) and arsenic (As). Since 1989 were reported by our group high concentrations of Pb in blood (PbB) and As in urine (AsU) in the local children. In present work, a Risk Communication Program (RCP) was generated to inform the children about the environmental risks of the site where they live, and to change conducts to diminish the exposure to Pb and As. We worked with 170 children (5 to 7 years) of the zone. The RCP was applied and the evaluation was realized by means of analysis of drawings, questionnaires and biological monitoring. In drawings of the children appeared toxic elements such as Pb, contaminated soil, cigarettes, among others. In the questionnaires applied to the children and family parents it was possible to estimate a change in the knowledge and in some conducts with regard to the pollutants, their effects and their exposure. There was not a decrease in the levels of PbB and in the levels of AsU. These were due probably because the principal route of exposure is not only the soil that had been contemplated previously.

[ effects of orally administered allicin on serum activity of some enzymes in experimental lead poisoning in common carp [cyprinus carpio]]

Lead poisoning in aquatic animals is of special importance, as is also true for all living creatures. Alicin, one of the main active components of garlic, is expected to play a protective role against lead poisoning, due to its abundant sulfur amino acids. This research studied the toxic effects of lead in Common carp focusing on blood serum enzyme activities. The study focused on five groups each including 46 Common carp [100 +/- 10g]. The groups 2-5 received lead acetate at 7mg/Lfor 10 days. Group 3 received 5mg allicin/KgBwt; and Group 4 received daily amounts of 10mg allicin/KgBwt, beginning 5 days before lead acetate was added. Group 5 received the same as Group 4, but received allicin for the same period as it received lead acetate. At the end of the experimental period a measurement was made of serum enzymes including GGT, ALT, AST, LDH and ALP. The studied parameters in Group 2, which was exposed to lead, were significantly higher when compared to the Control Group [p<0.001]. The enzyme activities in groups receiving allicin [Groups 3-5] were significantly, and dose dependently, less than those of Group 2. However, no significant differences were observed between Groups 4 and 5. The results of the present research suggest a potent effect for allicin in alleviating tissue injuries following lead poisoning

Plumbemia em trabalhadores da indústria de reciclagem de baterias automotivas da Grande Porto Alegre, RS / Blood lead levels in the battery recycling industry of the metropolitan region of Porto Alegre, RS

A reciclagem de baterias pode contaminar o ar, o solo e a água, não só no lugar de processamento, mas também nas regiões circunvizinhas, sendo que os resíduos permanecem no local mesmo após o término da atividade. No presente artigo descrevemos os resultados da avaliação da plumbemia em 53 operários que trabalhavam com reciclagem de baterias automotivas e em 53 indivíduos sem história de exposição. Os dados obtidos foram comparados e discutidos em relação às normas do Ministério do Trabalho (MT) e da Occupational Safety and Health Administration (OSHA). A plumbemia no sangue do grupo controle foi de 2,44±1,15 µg/dl e, no grupo exposto, de 59,43±28,34 µg/dl, sendo que 79,2 por cento dos indivíduos mostraram níveis acima do valor de referência (até 40 µg/dl). Estudos recentes recomendam estratégias para prevenir a intoxicação com chumbo: identificação, eliminação ou controle da fonte, monitoração da exposição e respectivos danos e um programa de recompra de baterias usadas das por parte da indústria de origem.

Battery recycling may contaminate soil, air and water not only at the processing site but also in the neighboring areas, inasmuch as the residues remain at the site even after the end of the activity. In the present article, we describe the results of plumbism evaluation in 53 individuals that work with car battery recycling and 53 individuals without history of lead exposure. The obtained data were compared and discussed according to the regulations of Brazilian Ministry of Labor and OSHA (Occupational Safety and Health Administration). Blood lead levels in the control group were 2.44 ± 1.15 µg/dl and 59.43 ± 28.34 µg/dl in the exposed group. 79.2 percent of the individuals presented levels above the reference value (40 µg/dl). Recent studies recommend strategies to prevent lead intoxication: source identification, control or elimination, monitoring of environmental exposure and hazards and a buy-back program of used batteries by the industry of origin.

Uso de los datos de plumbemia para evaluar y prevenir el envenenamiento infantil por plomo en Latinoamérica / Use of blood lead data in epidemiological studies to assess and prevent childhood lead poisoning in Latin America

La exposición al plomo es una amenaza seria para la salud de los niños, que se encuentra ampliamente distribuida en la Región de América Latina. Los funcionarios de salud pública necesitan identificar fuentes de exposición al plomo, así como sus efectos en la salud, para poder diseñar, implantar y evaluar las actividades preventivas y de control. Para evaluar la magnitud del problema del plomo es necesario definir tres elementos clave: a) las fuentes potenciales de exposición, b) los indicadores que se utilizarán para evaluar los efectos en la salud y la exposición en el medio ambiente, y c) las estrategias de muestreo de la población en riesgo. Se pueden utilizar varias estrategias con el fin de seleccionar la población blanco dependiendo de los objetivos del estudio, el tiempo límite y los recursos disponibles. Si el objetivo es evaluar la magnitud y las fuentes del problema pueden emplearse los siguientes métodos de muestreo: a) el muestreo al azar basado en la población; b) el muestreo al azar basado en las facilidades dentro de los hospitales, las guarderías o las escuelas; c) el muestreo objetivo de los grupos de alto riesgo; d) el muestreo de conveniencia (de voluntarios), y e) el reporte de los casos (éste puede conducir a la identificación de las poblaciones en riesgo, además de las fuentes de exposición). Para todos los diseños de muestreo, la información debe incluir tanto el uso de un cuestionario para el informe general de los participantes y de las fuentes potenciales locales de exposición, como la recolección de las muestras biológicas. En la interpretación de los datos se debe considerar el tipo de muestreo utilizado, el porcentaje de falta de respuesta y los factores que pueden influir en las mediciones del plomo en sangre, como la edad y la variación de la temporada. Las mediciones del plomo en la sangre se deben integrar dentro de una estrategia general para la prevención de toxicidad.

Determining lead sources in Mexico using the lead isotope ratio

OBJECTIVE: Lead poisoning can, in some cases, be traced to a specific route or source of exposure on the basis of the individual's blood lead isotope ratio. To assess the major source of lead exposure among women residing in Mexico City, we compared blood, ceramic, and gasoline lead isotope ratios. MATERIAL AND METHODS: The study population, randomly selected from participants of a large trial, (1/1996-12/1996) comprised of 16 women whose lead levels exceeded 10 æg/dl and who reported using lead-glazed ceramics. Lead isotope ratios were performed on a Perkin Elmer 5000 Inductively Coupled Plasma Mass Spectrometer (ICP-MS) interfaced with a Perkin Elmer HGA-600MS Electrothermal Vaporization System (ETV). RESULTS: The isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb) of both the blood specimens and their corresponding ceramic specimens were highly correlated, with r=0.9979, r²=0.9958, r=0.9957, r²=0.9915 and r=0.9945, r²=0.9890 values for the three isotope ratios, respectively, suggesting that the lead exposure most likely resulted from the use of these ceramic. Measurements of lead isotope ratios from leaded gasoline in use at the time of blood sampling, differed from those in blood and ceramics. CONCLUSIONS: Determining lead isotope ratios can be an efficient tool to identify a major source of lead exposure and to support the implementation of public health prevention and control measures.

Intervención ambiental en sitios contaminados por plomo: la experiencia en los Estados Unidos de América / Environmental intervention in sites contaminated by lead: the United States of America experience

Durante una década, los organismos estatales y federales han trabajado de manera conjunta con las comunidades a lo largo del territorio estadounidense, con el objeto de valorar el riesgo a la salud que implica la contaminación por plomo en las zonas residenciales. A menudo dichas comunidades han estado vinculadas con instalaciones destinadas anteriormente a actividades como la minería y la metalurgia; sin embargo, existen otras industrias como por ejemplo la fabricación de pinturas y el reciclaje de baterías, también identificadas como fuentes de contaminación por este metal. La vasta experiencia en las tareas de limpieza de los sitios contaminados ha puesto de manifiesto que los amplios programas destinados a identificar y manejar las vías de exposición pueden ayudar, de manera efectiva, a disminuir los niveles de plomo en sangre de las poblaciones más suceptibles, como la de los de niños en edades tempranas. Los programas de intervención ambiental son más efectivos cuando en las localidades afectadas se ejecutan programas de educación/intervención en salud, orientados al desarrollo de estrategias individualizadas para manejar el riesgo que implica la presencia de dicho metal en el ambiente.

Lead pollution and amelioration measures in the community of Frazers Content, St Catherine, Jamaica

Lead poisoning, especially in children, is a preventable disease. Many children are exposed to this hazard, especially in poor communities, because of a paucity of information on lead poisoning and increasing economic hardships. In 1994, the case of the poor suburban community of Frazers Content, St Catherine, Jamaica, came to the public attention because of the high frequency of hospital admissions, or outpatient treatment, of children for lead poisoning. This paper reviews a Blue Cross of Jamaica-led-initiative aimed at the clean up and education of the Frazers Content community. The following four-pronged approach was employed: environmental and biological sampling and sample analysis, health education, decontamination and community clean up and entrepreneurial activities. The project outputs included: training of 17 community wardens and 22 schoolteachers; the clean up of 64 residences which had lead levels in excess of 500 ppm; the establishment of an entombment site for the contaminated soil in accordance with the Jamaica Natural Resources Conservation Authority and training of residents in entrepreneurial skills, chicken and rabbit rearing and nursery establishment. The paper includes discussion of the lessons learnt and recommendations for future action.

Lead Level in Blood of Factories Workers in Syria

The level of lead in blood of Syrian workers in some industries was investigated. It is known that lead could be absorbed through all routes of exposure. Therefore, it is important to follow the level of lead in workers involved in batteries, petrol and paints industries. Lead concentration in blood was determined by atomic absorption. A total of 463 workers divided into 4 groups, in addition to 122 volunteers were screened for their lead level of blood. The results show that an extremely high concentration of lead was found in those working in batteries manufacturing [mean of 523 pg / L], whereas moderate elevation was found in workers involved in paints industry. However, petroleum industry workers showed slight increase in lead concentration but it was not significant. This study proved that many factors might affect lead level in blood, such as: age, duration of exposure, sex, wellbeing status and residence location. It is concluded that workers have lead concentration higher than 200 pg / L should not be in direct contact with any lead-containing product or by-product. The technology used in such industry must be upgraded, and environmental law should be strictly applied in all sectors of industry

Distúrbios neurológicos em trabalhadores com baixos níveis de chumbo no sangue. II- Disfunçöes neurocomportamentais / Neurological disturbances in workers with low levels of lead in the blood. II- Neuropsychological disorders

Trata-se de um estudo observacional, transversal, com populaçäo de estudo aleatorizada, cujo objetivo foi contribuir para a avaliaçäo da validade dos limites de tolerância biológica (LTB) estabelecidos no Brasil para a plumbemia (Pb-S) e a excreçäo urinária do ácido delta-aminolevulínico (ALA-U). Para tanto, foi aplicada uma variaçäo do WHO Neurobehavioral Core Test Battery a um grupo de trabalhadores expostos ao chumbo, cujos valores de Pb-S e ALA-U encontravam-se no momento - bem como nos 2 anos precedentes - abaixo dos LTB brasileiros. Os resultados foram comparados aos obtidos por intermédio da aplicaçäo da mesma bateria de testes, em um grupo-controle näo exposto ao chumbo. No grupo exposto foram encontrados sinais de comprometimento da memória, humor e coordenaçäo motora fina - que diferiam significativamente dos resultados obtidos no grupo-controle (p=0,02). Os resultados apontam contra a validaçäo dos LTB estabelecidos no Brasil para a Pb-S e a ALA-U

Distúrbios neurológicos em trabalhadores com baixos níveis de chumbo no sangue. I - Neuropatia periférica / Neurological disturbances in workers with low levels of lead in the blood. I - Peripheal neuropathy

Trata-se de estudo observacional, transversal, em populaçäo aleatorizada, cujo objetivo foi contribuir para a avaliaçäo da validade dos limites de tolerância biológica (LTB) estabelecidos no Brasil para a plumbemia (Pb-S) e a concentraçäo urinária do ácido delta-aminolevulínico (ALA-U). Para tanto, um grupo de trabalhadores expostos ao chumbo, cujos valores de Pb-S e ALA-U encontravam-se no momento do estudo - bem como nos 2 anos precedentes - abaixo dos LTB brasileiros, foi submetido a exame eletroneurográfico dos nervos mediano direto, ciático-popliteo externo direito, radial direito, radial esquerdo e sural direito. Os resultados foram comparados com os obtidos por intermédio da aplicaçäo do mesmo conjunto de exames em um grupo-controle näo exposto ao chumbo. No grupo exposto foram encontrados sinais de comprometimento dos nervos radiais - que diferiam significativamente dos resultados obtidos no grupo-controle (p=0,0067). Os resultados apontam contra a validaçäo dos LTB estabelecidos no Brasil para a Pb-S e a ALA-U

A inadequaçäo dos valores dos limites de tolerância biológica para a prevençäo da intoxicaçäo profissional pelo chumbo no Brasil / The inadequacy of threshold values for preventing lead poisoning in Brazil

Säo revisados os trabalhos que, a partir de 1975, estudaram a ocorrência de manifestaçoes neurológicas centrais e periféricas em trabalhadores ocupacionalmente expostos ao chumbo, que apresentavam níveis de exposiçäo supostamente insuuficientes para causarem saturnismo. É sugerido que os limites de tolerância biológica utilizados em nosso meio para firmar o diagnóstico de intoxicaçäo profissional pelo chumbo devam ser revistos. Tal sugestäo baseia-se na existência de evidência bem estabelecidas que apontam disfunçoes da conduçäo nervosa periférica e central, além de alteraçoes de várias funçoes nervosas superiores, em trabalhadores profissionalmente expostos ao chumbo que apresentam indicadores de efeito biológico e indicadores de exposiçäo inferiores aos limites estabelecidos pela legislaçäo brasileira.

Saturnismo: intoxicación por plomo / Saturnism: intoxication by plumb

El saturnismo es definido como la intoxicación aguda ó crónica por plomo o alguna de sus sales. Los autores hacen una amplia revisión sobre las características del plomo y sus componentes, su amplio uso en la industria y en infinidad de productos de uso en la vida diaria. Describen también su metabolismo y las alteraciones tóxicas que produce a nivel hematopeyético, sistema nervioso central, riñon y fibra muscular. Se revisa la clínica de esta entidad, en sus formas tanto crónica como aguda, y los métodos auxiliares de diagnóstico. Adicionalmente se revisan las bases del tratamiento actual y se, señalan pautas para la prevención de esta entidad en relación a trabajadores de plantas industriales, donde la incidencia es mayor.