Dietary risk assessment of drinking water and fish from cultivated wetlands of Ndop.

This study evaluated pesticide exposure practices, and the potential health risks of drinking water and consuming fish from the cultivated wetlands of Ndop, Cameroon. Six hundred and twenty-six questionnaires were conveniently administered to farmers (≥ 26 years old) in a cross-sectional study to assess exposure practices and dietary risks. The Chi-square and Pearson correlation coefficients were used to establish relationships between variables. The PRIMET model was used to predict a worst-case dietary risk. The pesticide handling practices of 90% of farmers were inadequate. Chlorpyriphos, lambda-cyhalothrin, fipronil, and paraquat dichloride posed a possible dietary risk at recommended and applied doses, with chlorpyrifos having the highest exposure toxicity ratio (ETRdiet = 36.72). Paraquat dichloride, fipronil, and lambda-cyhalothrin posed a possible dietary risk at 26.3%, 58.3%, and 62.2% of their recommended concentrations, respectively. Remarkably, the dietary risk for cypermethrin was acceptable at 5.8 times its recommended dose (ETRdietR = 0.29). The significant positive correlation (p = 0.000) between PECfish and ETRdiet, suggests a possible health risk of consuming fish and drinking water harvested from the wetlands, thus the need for replacing pesticides posing possible risks at lower or recommended concentrations with less toxic alternatives and to train farmers on pesticide application practices.

Climate change resiliency choices of small-scale farmers in Cameroon: determinants and policy implications.

Climate variability and change has continued to wreak havoc on the agricultural sector, with small-scale farmers being the most hard-hit. The limited adaptive capacity of small-scale farmers faced with the impacts of climate variability and change principally explains their high level of vulnerability. It is within this framework that this study sought to examine the specific resiliency choices of small-scale farmers faced with climate variability and change in Cameroon, and the plausible policy implications. Data was collected through a survey of 300 small-scale farmer household heads as well as climate data collected from meteorological stations. Data analysis was run on Microsoft Excel 2007 and SPSS 20, employing descriptive and inferential statistics. Findings showed significant fluctuations in climate parameters in recent years. The main resiliency choices of small-scale farmers faced with climate variability and change were on-farm practices (23%), off-farm practices (19%), and agroforestry practices (28%); with 30% of the sampled farmers taking to the no resiliency option. A statistically significant (p < 0.01; p < 0.05; and p < 0.10) causal and non-causal relationship was found to exist between independent variables (household size, age of household head, number of farms, farm size, household income, farm experience, gender, experience of extreme weather events, access to weather information, access to extension services, access to credit, distance to market, access to land, and membership in farming group) and small-scale farmers' practice of different resiliency options faced with climate variability and change. This shows that small-scale farmers' practice of different resiliency options faced with climate variability and change is determined by past experience of extreme weather/climate events as well as socio-economic and institutional factors. On the basis of these findings, it is recommended that policy makers factor in these determinants when taking actions geared towards enhancing small-scale farmers' resilience to climate variability and change.

Ecological risk assessment of agricultural pesticides in the highly productive Ndop flood plain in Cameroon using the PRIMET model.

Flood plains can make a significant contribution to food security due to their rich agricultural and aquaculture potentials but the misuse of pesticides in these ecosystems may seriously threaten their sustainability. We have assessed the risk of commonly used pesticides by rice and vegetable farmers on two major streams in the Ndop flood plain in Cameroon using the PRIMET model. Thirty pesticide formulations were identified containing 17 active ingredients belonging to fungicides (7), herbicides (3), and insecticides (7). Out of these, five posed acute and/or chronic risks to the streams. Chlorpyriphos-ethyl (ETR = 655), chlorothalonil (ETR = 250), and cypermethrin (ETR = 190) posed a definite acute risk to both streams. These pesticides also posed possible chronic risks with cypermethrin also posing a definite chronic risk (ETR = 1658) to fish in one of the streams. Mancozeb (ETR = 2.2) and λ-cyhalothrin (ETR = 2.8) posed a possible acute risk to both streams. It was interesting to note that most pesticides, including some of those that posed a risk, were applied at lower doses than their respective recommended doses. Differences in ETRs were also observed in the two streams with higher values occurring in the stream having a lower concentration of suspended solids. The higher velocity of the Ngwala-Mesaw stream did not affect the acute risk posed by pesticides. Pesticide toxicity was an important determinant in the risk posed and we recommend that appropriate mitigation measures be put in place to reduce the risk of these pesticides such as the implementation of an appropriate buffer zone between the edge of field and water body.