Polychlorinated dibenzo-p-dioxin (PCDDs) and polychlorinated dibenzofurans (PCDFs) in harbor sediments from Sea Lots, Port-of-Spain, Trinidad and Tobago.

Organochlorine compounds are a class of pollutants considered toxic to humans, fish and wildlife, and show great potential for accumulation and persistence in the environment. In May 1995, the United Nations Environmental Program (UNEP) Governing Council adopted Decision 18/32 (GC18/32) on persistent organic pollutants (POPs), the goal of which was to initiate an expeditious assessment process, initially beginning with twelve priority POPs: polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs or dioxins), polychlorinated dibenzofurans (PCDFs), aldrin, dieldrin, DDT, endrin, chlordane, hexachlorobenzene (HCB), mirex, toxaphene and heptachlor. In 1997, based on recommendations from the Intergovernmental Forum on Chemical Safety (IFCS), UNEP decided that immediate international action should be initiated to protect human health and the environment by reducing and/or eliminating emissions and discharges of the twelve persistent organic pollutants (the ‘dirty dozen’) specified by GC18/32. UNEP decision GC19/13C proposed a series of immediate action responses based on the IFCS recommendations: (1) general awareness of POPs; (2) information exchange between countries and organizations; and (3) improved availability of information and expertise on alternatives to POPs (UNEP, 2001 UNEP. 2001. The Stockholm Convention on Persistent Organic Pollutants. . English. PDF (accessed 29.09.08.).UNEP, 2001). In accordance with the mandates of UNEP GC18/32, GC19/13C and GC20/24, the first global legally binding instrument on POPs, ‘The Stockholm Convention’, was agreed upon. Trinidad and Tobago declared its accession to this in December 2002 and the Convention became legally binding in 2004 after France became the fiftieth country to ratify the agreement...

The effects of the environment on autistic spectrum disorder in Jamaica

OBJECTIVE: The prevalence of autistic disorder has been rising worldwide. This disorder is believed to have a genetic basis with an environmental trigger. The clinical presentation has features that are similar to mercury poisoning, suggesting a probable environmental trigger. This paper investigates the relationship between environmental contaminants/toxins, including mercury, and autistic disorder in Jamaica. METHODS: Autistic children were identified from public and private hospital records and from records of special schools. Fifty-eight parents of autistic children completed a questionnaire about their environment and frequency of exposure to harmful chemicals and contaminants during pregnancy and prior to diagnosis. The childhood Autism Rating Scale determined the severity of autistic disorder. The relationship between the severity of autism and different environmental factors was analyzed using the chi-squared test. RESULTS: The meanñStandard Deviation age of autistic children was 6.5ñ3.7 years. There were 79 percent male and 21 percent female. Although there were rates of autism calculated by parish, there are no known apparent links between the geographical region and severity of autism. Sixty percent of the population had changed their address since birth. No association was found between use of common household chemicals (eg bleach, disinfectant), residence close to possible environmental contaminants (eg garbage dumps, factories, bodies of water) and autism, either during pregnancy or prior to diagnosis. A single case of exposure to mercury during pregnancy associated with severe autism was identified. CONCLUSIONS: This study was unable to identify any associations between a number of environmental agents and the severity of autism. The single case of mercury exposure during pregnancy warrants further investigation of this association with a larger sample size (AU)

Organochlorine contaminants in Morelet's crocodile (Crocodylus moreletii) eggs from Belize

Non-viable eggs of Morelet's crocodile (Crocodylus moreletti) were collected from Gold Botton (GBL) and New River lagoons (NRL) in northern Belize and screened for organochlorine (OC) compounds using gas chromatography (GC) with electron capture detection (ECD). All egg samples from both lagoons (n=24) tested positive for one or more OCs. Primary contaminants were p,p-DDE and methoxychlor, detected in 100 percent and 29 percent of the eggs examined, respectively. Concentrations of individual OC contaminants ranged from 1 ppb (ng chemical/g egg). Total concentrations of OCs (sum of all OCs) for one egg collected from a nest at GBL reached as high as 0.7 ppm. Sediment samples from both lagoons also tested positive for OCs (lindane, aldrin, methoxychlor, heptachlor epoxide, p, p-DDT, among others). Nest media (soil and plant material) collected from crocodile nests at GBL were positive for p, p-DDT, methoxychlor, aldrin, endosulfan II, and endrin aldehyde. Based on the 24 egg samples analyzed to date, crocodiles from both lagoons are being exposed to OCs. Such exposure may present a health threat to populations of crocodiles in Central America. (AU)