Pesticides use by smallholder farmers in vegetable production in Northern Tanzania.

Small-scale farmers in Northern Tanzania grow vegetables that include tomatoes, cabbages and onions and use many types of pesticides to control pests and diseases that attack these crops. Based on the use of questionnaires and interviews that were conducted in Arumeru, Monduli, Karatu, and Moshi rural districts, this study investigates farmers' practices on vegetable pest management using pesticides and related cost and health effects. The types of pesticides used by the farmers in the study areas were insecticides (59%), fungicides (29%) and herbicides (10%) with the remaining 2% being rodenticides. About a third of the farmers applied pesticides in mixtures. Up to 90% had a maximum of 3 pesticides in a mixture. In all cases there were no specific instructions either from the labels or extension workers regarding these tank mixtures. Fifty three percent of the farmers reported that the trend of pesticide use was increasing, while 33% was constant and 14% was decreasing. More than 50 percent of the respondents applied pesticides up to 5 times or more per cropping season depending on the crop. Insecticides and fungicides were routinely applied by 77% and 7%, respectively by these farmers. Sixty eight percent of farmers reported having felt sick after routine application of pesticides. Pesticide-related health symptoms that were associated with pesticides use included skin problems and neurological system disturbances (dizziness, headache). Sixty one percent of farmers reported spending no money on health due to pesticides. These results can be used to develop a tool to quantify the cost of pesticide use in pest management by small-scale vegetable farmers in Northern Tanzania and contribute to the reformation of pesticide policy for safe and effective use of pesticides.

Knowledge, attitudes and practices (KAP) among agricultural extension workers concerning the reduction of the adverse impact of pesticides in agricultural areas in Tanzania.

BACKGROUND: Extension workers are educated locally to enable them to train farmers in using improved local farming methods and imported technology, such as pesticides, to increase crop production. However, the extension workers are not adequately trained in health aspects of pesticides and hence are unable to provide adequate services to farmers with regard to safe use of pesticides. OBJECTIVE: The present study assessed the knowledge, attitudes and practices of agricultural extension workers with respect to health effects of pesticides in order to develop strategies for the control of pesticide exposure and prevention of pesticide poisoning in Tanzania. METHODS: A survey of Tanzanian agricultural extensionists was undertaken in 1991-1994 using a standardized questionnaire in face-to-face interviews. Extensionists who were district agricultural officers, assistant agricultural officers, agricultural assistants, and field assistants, working in the coffee and cotton growing areas (N = 61) within a radius of 15 km of farm, estate or village under farm worker study (reported elsewhere) were included in the survey. RESULTS: The majority of extensionists knew that pesticides could enter the human body but only a quarter perceived pesticides as a major problem in the community they served. The majority showed awareness of potential health hazards of the different pesticides used in their service areas, but they did not recognize what pesticides were responsible for poisoning. A high proportion was familiar with first aid procedures in case of pesticide poisoning; however, many procedures described were not appropriate for pesticide poisoning. CONCLUSIONS: The survey indicated that training of agricultural workers in health aspects of pesticide exposure is an important task for adequate provision of service to farmers with regard to safe use of pesticides in Tanzania. Nevertheless, the appropriate role of extensionists in reducing the health impact of pesticides would be to advocate pesticides of low toxicity or non-chemical pest control.

Acute health effects of organophosphorus pesticides on Tanzanian small-scale coffee growers.

Acute health effects of organophosphorus (OP) pesticides on coffee farmworkers in 1991-1992 in Tanzania are reported to provide a basis for concern over farmworkers being overexposed during application. Workers exposed to OP pesticides (N=133) were drawn from a population of about 240,000 coffee farmers. They were interviewed on symptoms and personal protection, and their erythrocyte acetylcholinesterase (AChE) activity was determined during both spraying and nonspraying period. AChE activities during spraying and nonspraying period were comparable (mean 32.0, SD 7.8 vs. 33.0, SD 8.7 U/g HgB, P=0.26). The prevalence of cough, headache, abdominal pain, excessive sweating, nausea, excessive salivation, diarrhea, and vomiting did not differ significantly between spraying and nonspraying periods. There was no suggestion of decreased AChE in exposed subjects who complained of OP-related symptoms compared to symptomless exposed subjects. Use of gloves, long boots, head cover, face cover, and coverall was not significantly associated with AChE activity. No marked AChE depression was found during spraying season, which may explain the lack of association between symptoms and AChE. The fact that only moderately toxic OP pesticides were used may indicate that toxicity was not sufficiently high to cause depression. Experience, however, suggests that occupational poisoning remains a potential serious danger in coffee cultivation in Tanzania.

Assessment of the ability of health care providers to treat and prevent adverse health effects of pesticides in agricultural areas of Tanzania.

A survey of Tanzanian health care providers in agricultural areas was undertaken in 1991-1994 to assess their knowledge of toxic effects of pesticides, experiences and practices, as well as of their needs for appropriate information in order to develop effective strategies for reducing pesticide poisoning. Face-to-face interviews were conducted with 104 physicians, clinical officers and nurses at health care facilities in the coffee and cotton growing areas. Eighty percent of respondents reported to have seen one and nine of them two to four cases of pesticide poisoning in the preceding three months. A significantly higher annual number of poisonings were observed in coffee than in cotton area (GM 0.5 vs 0.1). Also the number of cases registered in hospitals was considerably higher than that in the out-patient health care (GM 1.7 vs 0.2). Pesticide poisoning was regarded as a major problem in the community by 63% of health care providers, including 77% of hospital staff. One third of health care providers thought that a certain percent of pesticide poisoning cases remain unrecognized, and that this percentage is higher in cotton than in coffee growing areas. The respiratory tract was the major route for pesticide to enter the human body; this was followed by gastrointestinal tract, skin, and eyes. Only one percent of the respondents could identify the groups of pesticides (organophosphate vs organochlorine) mostly used in the study areas. The survey indicated that training of hospital staff in toxicity of pesticide exposure is an important task and a prerequisite for efficient recognition, diagnosis and treatment of pesticide poisoning cases in Tanzania.

Pesticide-handling practices in agriculture in Tanzania: observational data from 27 coffee and cotton farms.

The practices of pesticide handling in agriculture were surveyed in 1991-1993 in Tanzania, to identify hazardous practices and farms where they occurred. The study involved 23 coffee farms with 246 persons exposed to hazardous practices, and four cotton farms with 45 exposed. An observation form addressed locations of important places with respect to pesticide spraying, storage, disposal, and equipment; personal protection; and hygiene. More pesticide formulations were used for coffee compared with cotton and by individual rather than cooperative farms. Coffee farms more often had unlabeled pesticide containers and missing mixing instructions, while cotton pesticides were stored in bedrooms, near food, and near open fires, and pesticide leftovers were often present. Hazardous practices were more pronounced at individual than cooperative farms, with significant differences in pesticide storage areas, as well as unlabeled and non-original containers. The study demonstrated the need to train farmers in pesticide safety, strengthen advisory and regulatory services, and extend protection to farm workers' families.

Collaboration between developing and developed countries and between developing countries in occupational health research and surveillance.

Collaborative occupational health and safety studies between counterparts in developing and developed countries and between developing countries have demonstrated their potential for improving occupational health and safety. Such collaboration in occupational health and safety is encouraged in the development of infrastructure in research empowerment and capacity building. This action includes the setting of priorities, the identification and documentation of problems, sponsorship, data bases and surveillance systems, technical support, methodology, publishing, research and training programs, controlled intervention, information exchange, and networking. Examples of priorities in occupational health and safety in the developing world include the informal sector (informally hired and independent workers), temporary work, pesticides, accidents, dusts, carcinogens, solvents, ergonomics, women and child labor, human immunodeficiency virus/acquired immunodeficiencey syndrome (HIV/AIDS), and transfer of hazardous materials and technologies. The sustainability of occupational health and safety structures and functions in the developing countries is a primary concern. Socioethical principles emphasize local, national, mutual and global gains. Examples of collaboration are given. Pervasive problems and strategies toward their solution are highlighted.