Résumé
In Nigeria, some of the environmental factors that may predispose to cancer risk are- unsafe water supplies, untreated sewage, sullage, industrial effluents and emissions. Household hazardous wastes (e.g. batteries, paints, Cytotoxic / genotoxic drugs, etc.), use of cooking fuels (e.g. firewood, charcoal and kerosene), roasted foods, and diesel/petrol generators contribute to cancer causing chemicals particularly polycyclic aromatic hydrocarbons (PAH), benzene derived byproducts, heavy metals etc. in the immediate vicinity of the households irrespective of socioeconomic status of the population. These agents spread the cancer causing chemicals into the environment both outer and built environment. Other emerging issues are the water disinfectant chemicals, arsenic, hormones and drug residues, PAH, dioxins and furans which are proven carcinogens. In addition, leachates (liquid effluents) from the waste dumpsites find their way into terrestrial and aquatic ecosystems and return to human body through food chain. Ecosystems are degraded resulting in biodiversity loss and bioaccumulation of toxic substances. In Niger Delta region, oil spillage and gas flaring activities have been causing morbidity among women and children. Changing lifestyle also plays a role in cancer increase as evident from colorectal cancers. Cancer of the lung, skin, and prostate were more reported from Niger Delta region than other areas in south-west. More evidence is shifting towards the environment as a major cause in cancer incidence. The Nations’ tertiary Institutions lack adequate facilities to detect some of the environmental chemicals which may be suspected carcinogens. There is need to strengthen Research & Development activities in Environmental Toxicology and move ahead in line with the emerging environmental threats to health particularly, cancers.
Keywords: Cancer, built environment, water, polycyclic aromatic hydrocarbons, carcinogens, waste management
Résumé
Au Nigeria, certains facteurs environnementaux prédisposant les risques du cancer inclus la qualité de l’eau, les eaux usées, les émissions industrielles. Les déchets domestiques (batteries, peintures, médicaments cytotoxiques / génotoxiques, etc.), usage des gaz a chauffage (bois, charbon et pétrole), Les aliments fumes et les générateurs a diesel/essence contribuent au cancer particulièrement les hydrocarbonés polycyclique aromatisées tels que les produits dérivé du benzène et les métaux lourds dans notre environnement mis a part le statut socioéconomique de la population. Ces substances augmentent l’incidence du cancer dans notre environnement. D’autres issues émergeant incluent les désinfectants chimiques, arsénite, les résidus des hormones et des médicaments, dioxine et les furanes qui sont démontrés carcinogeniques. En plus, les liquides effluents dans les sites de dépôt d’ordures entrainé dans les écosystèmes terrestre et aquatiques et retourne dans le corps humain par la chaine alimentaire. Les écosystèmes sont dégradés résultant une perte de la biodiversité et la bioaccumulation des substances toxiques. Dans la région du Niger Delta, les activités pétrolières continues de causer la souffrance parmi les femmes et les enfants. Changer le style de vie peut aussi augmenter les causes du cancer telque les cancers colorectaux. Le cancer des poumons, de la peau, de la prostate étaient plus reports dans cette région que d’autres régions au sud-ouest. Plus d’évidences est retourné vers l’environnent comme cause majeur de l’incidence du cancer. Les institutions tertiaires nationales manquent les infrastructures adéquates pour détecter les polluants environnementaux suspectes carcinogeniques. Il est nécessaire de supporter les activités de recherche et de développement en toxicologie environnementale et cancer.
Correspondence: Prof. MKC Sridhar, Division of Environmental Health Sciences, Department of EMSEH, Faculty of Public Health, College of Medicine, University of Ibadan, Ibadan, Nigeria. E-mail: mkcsridhar@yahoo.com
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