Exposure to air pollutants and heat stress among resource-poor women entrepreneurs in small-scale cassava processing.

Exposure to air pollutants and heat stress from traditional cooking fires is the leading cause of mortality and morbidity in low- and middle-income countries globally and have an adverse effect on the environment. According to the World Health Organization, 3.8 million people die annually prematurely from illness related to household air pollution. Families living in poverty are at the highest risk, especially women and children. In this study, exposure to particulate matter (PM2.5 and PM10), carbon monoxide (CO) and nitrogen dioxide (NO2) was measured among resource-poor women cassava processors. The test locations were chosen in the peri-urban settlements of Abeokuta in the Ogun State of Nigeria, where household women entrepreneurs roast garri (granulated cassava) for sale in the local market. The measurements were taken for two types of stoves which are generally existing in the study location. First, a rectangular stove (RS) with two operators and, second, a circular stove (CS) with one operator; both stoves used wood as fuel. The emissions were compared with a modern mechanical liquefied petroleum gas burner-based garri roaster (GS). Hours spent per day in front of garri stoves ranged from 6 to 12 h for both stoves, with a frequency of 1 to 3 days of operation per week. It was found that CS operators were spending significantly more time in producing garri, which is due to the low capacity of the CS. The average PM2.5 concentrations for RS and CS were 381 and 273 µg/m3, respectively, estimated to be 21 and 41 µg/m3 on an annual mean level basis. Similarly, for PM10, the mean concentration levels were 1580 and 594 µg/m3 for RS and CS, respectively. The annual mean levels for PM10 were about 89 µg/m3 for both types of stoves. CO exposure during garri processing was up to five times higher than the recommended concentrations with a 4-h mean of 48 and 50 mg/m3 for RS and CS, respectively. NO2 levels were very low, ~ 0 ppm. This investigative research concluded that wood-fired small-scale garri producers in Nigeria are exposed to very unhealthy levels of PM, CO and thermal stress. The concentration levels of both PM and CO were exceeding the global as well as Nigerian ambient air quality standard regulations. Along with air pollution, thermal stress was a significant issue, which is known to exacerbate the negative effect of air pollution on the human body.

Safety of Yam-Derived (Dioscorea rotundata) Foodstuffs-Chips, Flakes and Flour: Effect of Processing and Post-Processing Conditions.

The production of yam-derived (Dioscorea rotundata) foodstuffs is mainly performed by small and medium scale processors that employ old traditional methods. This can lead to differences in quality from processor to processor, and from location to location, with consequent safety concerns. As such, the effects of processing and post-processing phases (i.e., storage, transport, etc.) on the safety of some yam-derived foodstuffs-namely chips, flakes, and flour-has been evaluated, with a focus on bacterial and fungal contamination, aflatoxins, pesticides, and heavy metals (Pb, Ni, Cd and Hg). Yams harvested and processed in Nigeria were screened, being that the country is the largest producer of the tuber, with 70⁻75% of the world production. Results highlighted no presence of pesticides, however, many samples showed high levels of bacterial and fungal contamination, together with heavy metal concentrations above the recommended safety levels. No trend was observed between the items considered; it was noticed, however, that samples purchased from the markets showed higher contamination levels than those freshly produced, especially regarding bacterial and aflatoxins presence. The processing stage was identified as the most critical, especially drying. Nonetheless, post-processing steps such as storage and handling at the point of sale also contributed for chemical contamination, such as aflatoxin and heavy metals. The results suggested that both the processing and post-processing phases have an impact on the safety of yam chips, flakes, and flour.