Exposição a contaminantes ambientais durante a gestação e seus efeitos sobre a saúde fetal: uma revisão de literatura

Human exposure to environmental contaminants is omnipresent. A great concern about individuals who live near hazardous waste sites is the potential risk of adverse pregnancy outcomes, especially birth defects. Additionally, with the exception of mercury, lead and PCBs, there is not clear evidence of the teratogenicity caused by other environmental contaminants due to methodological difficulties. Unlike animal experiments, people are rarely exposed to a single hazardous contaminant. However, most of the information documenting adverse reproductive health effects from environmental contaminants originated from studies focused on exposure to single chemicals, and there is little information available on how two or more contaminants affect human pregnancies. This paper reviews the methodological approaches used to access the adverse outcomes of pregnancies exposed to environmentalcontaminants and its major results.A exposição humana a contaminantes ambientais é onipresente. Uma grande preocupação em relação à população que vive perto de fontes poluentes é o risco potencial de efeitos adversos para as gestações, especialmente defeitos congênitos. Excetuando-se o mercúrio, o chumbo e os bifenis pliclorinados (PCBs), não há uma evidência clara de teratogenicidade causada por outros contaminantes ambientais, possivelmente devido a dificuldades metodológicas. Contrariamente ao que ocorre em experimentos com animais de laboratório, as pessoas são raramente expostas a um único contaminante potencialmente perigoso. Porém, a maioria das informações que documentam efeitos adversos secundários à contaminação ambiental na saúde reprodutiva são oriundas de exposição a somente um agente e há pouca informação disponível sobre de que maneira dois ou mais contaminantes ambientais podem afetar a  gestação. Este artigo revisará as abordagens metodológicas utilizadas para  se dispor de um acesso aos resultados adversos decorrentes da exposição aos poluentes e seus principais resultados

Avaliação de teratógenos potenciais na população brasileira: a experiência do Sistema Nacional de Informação sobre Agentes Teratogênicos em Porto Alegre (SIAT)

The National System of Information about Teratogenic Agents (SIAT) was set up in Porto Alegre, Southern Brazil, in 1990, with the purpose of providing doctors and the general public with rapid and updated information about the reproductive risks related to exposure  to teratogenic agents. SIAT, which was the first service of this kind to operate in Latin America, is also an important source of data for prospective investigations about teratogenicity in humans. In this paper we report the experience of this service during its first eleven years and its possible contributions. The introduction in the following years of similar services in other Brazilian cities (Rio de Janeiro, São Paulo and Salvador) and the operation of all four services within an integrated and coordinated national network enhance the potential of this service regarding health care and research.O Sistema Nacional de Informações sobre Agentes Teratogênicos (SIAT) foi implantado em Porto Alegre, Rio Grande do Sul, em 1990, com a proposta de fornecer a médicos e à população em geral informações rápidas e atualizadas sobre os riscos reprodutivos relacionados à exposição a agentes teratogênicos. O SIAT, que foi o primeiro serviço deste tipo a operar na América Latina também é uma importante fonte de dados para investigações prospectivas sobre teratogenicidade em humanos. Neste artigo nós relatamos a experiência deste serviço nos seus primeiros 11 anos de funcionamento e suas possíveis contribuições. A introdução em anos posteriores de outros três serviços similares em outras três capitais brasileiras (Rio de Janeiro, São Paulo e Salvador), faz com que a integração destes quatro serviços dentro de uma rede nacional coordenada aumente o potencial do SIAT tanto no que diz respeito a cuidados de saúde como à pesquisa.&nbsp

Epidemiological surveillance of birth defects compatible with thalidomide embryopathy in Brazil

The thalidomide tragedy of the 1960s resulted in thousands of children being born with severe limb reduction defects (LRD), among other malformations. In Brazil, there are still babies born with thalidomide embryopathy (TE) because of leprosy prevalence, availability of thalidomide, and deficiencies in the control of drug dispensation. Our objective was to implement a system of proactive surveillance to identify birth defects compatible with TE. Along one year, newborns with LRD were assessed in the Brazilian hospitals participating in the Latin-American Collaborative Study of Congenital Malformations (ECLAMC). A phenotype of LRD called thalidomide embryopathy phenotype (TEP) was established for surveillance. Children with TEP born between the years 2000-2008 were monitored, and during the 2007-2008 period we clinically investigated in greater detail all cases with TEP (proactive period). The period from 1982 to 1999 was defined as the baseline period for the cumulative sum statistics. The frequency of TEP during the surveillance period, at 3.10/10,000 births (CI 95%: 2.50-3.70), was significantly higher than that observed in the baseline period (1.92/10,000 births; CI 95%: 1.60-2.20), and not uniformly distributed across different Brazilian regions. During the proactive surveillance (2007-2008), two cases of suspected TE were identified, although the two mothers had denied the use of the drug during pregnancy. Our results suggest that TEP has probably increased in recent years, which coincides with the period of greater thalidomide availability. Our proactive surveillance identified two newborns with suspected TE, proving to be a sensitive tool to detect TE. The high frequency of leprosy and the large use of thalidomide reinforce the need for a continuous monitoring of TEP across Brazil.Instituto Multidisciplinario de Biología Celula

Epidemiological surveillance of birth defects compatible with thalidomide embryopathy in Brazil

The thalidomide tragedy of the 1960s resulted in thousands of children being born with severe limb reduction defects (LRD), among other malformations. In Brazil, there are still babies born with thalidomide embryopathy (TE) because of leprosy prevalence, availability of thalidomide, and deficiencies in the control of drug dispensation. Our objective was to implement a system of proactive surveillance to identify birth defects compatible with TE. Along one year, newborns with LRD were assessed in the Brazilian hospitals participating in the Latin-American Collaborative Study of Congenital Malformations (ECLAMC). A phenotype of LRD called thalidomide embryopathy phenotype (TEP) was established for surveillance. Children with TEP born between the years 2000-2008 were monitored, and during the 2007-2008 period we clinically investigated in greater detail all cases with TEP (proactive period). The period from 1982 to 1999 was defined as the baseline period for the cumulative sum statistics. The frequency of TEP during the surveillance period, at 3.10/10,000 births (CI 95%: 2.50-3.70), was significantly higher than that observed in the baseline period (1.92/10,000 births; CI 95%: 1.60-2.20), and not uniformly distributed across different Brazilian regions. During the proactive surveillance (2007-2008), two cases of suspected TE were identified, although the two mothers had denied the use of the drug during pregnancy. Our results suggest that TEP has probably increased in recent years, which coincides with the period of greater thalidomide availability. Our proactive surveillance identified two newborns with suspected TE, proving to be a sensitive tool to detect TE. The high frequency of leprosy and the large use of thalidomide reinforce the need for a continuous monitoring of TEP across Brazil.Instituto Multidisciplinario de Biología Celula

Epidemiological Surveillance of Birth Defects Compatible with Thalidomide Embryopathy in Brazil

The thalidomide tragedy of the 1960s resulted in thousands of children being born with severe limb reduction defects (LRD), among other malformations. In Brazil, there are still babies born with thalidomide embryopathy (TE) because of leprosy prevalence, availability of thalidomide, and deficiencies in the control of drug dispensation. Our objective was to implement a system of proactive surveillance to identify birth defects compatible with TE. Along one year, newborns with LRD were assessed in the Brazilian hospitals participating in the Latin-American Collaborative Study of Congenital Malformations (ECLAMC). A phenotype of LRD called thalidomide embryopathy phenotype (TEP) was established for surveillance. Children with TEP born between the years 2000–2008 were monitored, and during the 2007–2008 period we clinically investigated in greater detail all cases with TEP (proactive period). The period from 1982 to 1999 was defined as the baseline period for the cumulative sum statistics. The frequency of TEP during the surveillance period, at 3.10/10,000 births (CI 95%: 2.50–3.70), was significantly higher than that observed in the baseline period (1.92/10,000 births; CI 95%: 1.60–2.20), and not uniformly distributed across different Brazilian regions. During the proactive surveillance (2007–2008), two cases of suspected TE were identified, although the two mothers had denied the use of the drug during pregnancy. Our results suggest that TEP has probably increased in recent years, which coincides with the period of greater thalidomide availability. Our proactive surveillance identified two newborns with suspected TE, proving to be a sensitive tool to detect TE. The high frequency of leprosy and the large use of thalidomide reinforce the need for a continuous monitoring of TEP across Brazil