Pesticides, Anthropogenic Activities, History and the Health of Our Environment: Lessons from Africa

This chapter describes the historical events related to pesticide use. The description of events focuses on human activities that necessitated the use of chemical agents for pest control to protect crops, and animals including humans in African countries. The description covers the common pests in Africa and the need for pest control using pesticides. History of pesticide use in Africa and the ban of organochlorines are covered. Controversies under discussion in Africa and the current trend of pesticide use in Africa are part of the chapter as well as pesticide import and supply. Hazard and risk of exposure of biological organisms including humans to pesticides due to anthropogenic activities in Africa and pros and cons of pesticide use in Africa are covered

Association of Long-Term Pesticide Exposure and Biologic Parameters in Female Farm Workers in Tanzania: A Cross Sectional Study

The study aimed to assess the association of long-term pesticide exposure (≥5 years) with hematological, serum biochemical parameters and acetylcholinesterase activity in farm workers. These pesticides included organophosphorus pesticides, carbamates, pyrethroids, dithiocarbamates, and other pesticides such as endosulfan. Applying a cross-sectional study design, 69 females from a pesticide-exposed farm population and 30 females from a district not using pesticides (reference group) were studied. The mean red cell corpuscular volume and hematocrit values were significantly lower (74.7 ± 9.1 fl; 95% CI 72.5–76.9 and 32.0% ± 4.6%; 95% CI 30.9–33.1, respectively) in the exposed compared to the reference group, whereas mean corpuscular hemoglobin concentration and platelets were significantly higher (37.4 ± 3.8 g/dL; 95% CI 36.5–38.3 and 374.1 ± 95.3/L; 95% CI 351.2–396.9, respectively) in the exposed compared to the reference group. Mean serum glutamic oxaloacetate transaminase (20.7 ± 8.9 U/L; 95% CI 18.5–22.9) and creatinine (83.9 ± 6.6 μmol/L; 95% CI 82.3–85.5) were significantly higher in the exposed compared to the reference group. A higher mean esterase activity (AChE 0.6 ± 0.2 mM/min/mg protein; 95% CI 0.56–0.7; BChE 0.9 ± 0.4 mM/min/mg protein; 95% CI 0.9–1.1) was noted in the exposed group. Regression models suggest that occupational exposure (p < 0.001) could be a predictor of esterase (AChE and BChE) activity and biochemical changes (β = 0.4, 95% CI: 0.3–0.5; β = 0.7, 95% CI: 0.6–0.9, respectively). Long-term pesticide exposure affects the hemato-biochemical and esterase responses, establishing the need for further studies

Self-Reported Symptoms and Pesticide Use among Farm Workers in Arusha, Northern Tanzania: A Cross Sectional Study

The objective of the study was to describe self-reported health symptoms, the use of personal protective gear and clothing and poor safety procedures when applying pesticides among farm workers. A total of 128 adult farm workers were interviewed using a structured questionnaire during the farming season. The commonly used pesticides included profenofos, mancozeb, chlorpyrifos, cypermethrin, deltamethrin, permethrin, lambda-cyhalothrin, endosulfan and carbosulfan. The majority (>90%) of farm workers used no personal protective clothing while handling pesticides. More than one-third of farm workers ate and drank without washing their hands following pesticide handling, while a smaller number smoked or chewed gum. Wearing special boots during pesticide application was found to reduce the risk of skin rash (OR = 0.2, 95% CI: 0.06–0.66), whereas smoking when applying pesticides increased the risk of chest pain occurrence (OR = 4.0, 95% CI: 1.14–15.43), as well as forgetfulness (OR = 4.0, 95% CI: 1.30–14.02). Chewing gum and eating when applying pesticides was associated with diarrhoea (OR = 11.0, 95% CI: 1.80–6.84 and OR = 7.0, 95% CI: 1.27–3.67 respectively). The increased self-reported prevalence of post-exposure adverse health effects among farm workers was associated with poor use of personal protective clothing and poor safety practices during pesticide use and handling. These data indicate the need for improved availability and use of protective equipment, and training in crop and pest management practices to prevent risky behavioursand for safer and sustainable vegetable production

Prenatal exposure to persistent organic pollutants in Northern Tanzania and their distribution between breast milk, maternal blood, placenta and cord blood

Human exposure to persistent organic pollutants (POPs) begins during pregnancy and may cause adverse health effects in the fetus or later in life. The present study aimed to assess prenatal POPs exposure to Tanzanian infants and evaluate the distribution of POPs between breast milk, maternal blood, placenta and cord blood. For assessment of prenatal exposure, 48 maternal blood samples from Mount Meru Regional Referral Hospital (MMRRH), Arusha Tanzania, were analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs), dioxin-like (DL) activity and perfluorinated alkyl substances (PFASs). For evaluation of POPs distribution between maternal/infant compartments, breast milk, placenta and cord blood corresponding to the maternal blood were analyzed for OCPs, PCBs and BFRs. In maternal blood, p,p´- DDE was detected in 100% of the samples ranging between 29 and 1890 ng/g lipid weight (lw). PCB-153 was the only PCB detected in maternal blood, with detection rate of 29% and concentrations up to 116 ng/g lw. BDE-47 was detected in 65% of the maternal blood samples, ranging betweenacceptedVersio

Randomized controlled safety and efficacy trial of 2 vitamin A supplementation schedules in Tanzanian infants.

BACKGROUND: Vitamin A supplementation reduces morbidity and mortality in children living in areas endemic for vitamin A deficiency. Routine vitamin A supplementation usually starts only at age 9 mo, but high rates of illness and mortality are seen in the first months of life. OBJECTIVE: The objective of the study was to evaluate the safety and efficacy of vitamin A supplementation at the same time as routine vaccination in infants aged 1-3 mo. DESIGN: We recruited 780 newborn infants and their mothers to a randomized double-blind controlled trial in Ifakara in southern Tanzania. In one group, mothers received 60,000 microg vitamin A palmitate shortly after delivery, and their infants received 7500 microg at the same time as vaccinations given at approximately 1, 2, and 3 mo of age. In the other group, mothers received a second 60,000-microg dose when their infant was aged 1 mo, and their infants received 15,000 microg at the same time as the routine vaccinations. VAD was defined as a modified relative dose-response test result of >or=0.060. RESULTS: High-dose vitamin A supplementation was well tolerated. The relative risk of VAD at 6 mo in the high-dose group compared with the lower dose group was 0.91 (95% CI: 0.76, 1.09; P=0.32). Serum retinol and incidence of illness did not differ significantly between the 2 groups. Some vitamin A capsules degraded toward the end of the study. CONCLUSIONS: Doubling the doses of vitamin A to mothers and their young infants is safe but unlikely to reduce short-term morbidity or to substantially enhance the biochemical vitamin A status of infants at age 6 mo. The stability of vitamin A capsules merits further investigation

Prenatal exposure to persistent organic pollutants in Northern Tanzania and their distribution between breast milk, maternal blood, placenta and cord blood

Human exposure to persistent organic pollutants (POPs) begins during pregnancy and may cause adverse health effects in the fetus or later in life. The present study aimed to assess prenatal POPs exposure to Tanzanian infants and evaluate the distribution of POPs between breast milk, maternal blood, placenta and cord blood. For assessment of prenatal exposure, 48 maternal blood samples from Mount Meru Regional Referral Hospital (MMRRH), Arusha Tanzania, were analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs), dioxin-like (DL) activity and perfluorinated alkyl substances (PFASs). For evaluation of POPs distribution between maternal/infant compartments, breast milk, placenta and cord blood corresponding to the maternal blood were analyzed for OCPs, PCBs and BFRs. In maternal blood, p,p´- DDE was detected in 100% of the samples ranging between 29 and 1890 ng/g lipid weight (lw). PCB-153 was the only PCB detected in maternal blood, with detection rate of 29% and concentrations up to 116 ng/g lw. BDE-47 was detected in 65% of the maternal blood samples, ranging betwee