Evaluation of organochlorine pesticide residues in Beta vulgaris, Brassica oleracea, and Solanum tuberosum in Bloemfontein markets, South Africa.

This study evaluated the level of selected pesticide residues in the staple vegetables; Brassica oleracea var. capitata (cabbage), Beta vulgaris var. cicla (Swiss chard), and Solanum tuberosum (potato) from fresh produce markets in the city of Bloemfontein, South Africa. A QuEChERS extraction method was used followed by quantitation using GC-HRT/MS. The pesticide residues were detected in levels lower than the recommended Maximum Residue Levels ranging from not detected to 121.6 ng/kg recorded for heptachlor in cabbage samples. Cabbage was generally susceptible to pesticide residue accumulation with the average total concentration for different markets at 222 mg/kg. The pesticide residues were predicted to be from recent applications but their existence within guideline limits indicated that their use in vegetable farming was within the FAO/WHO recommended good agricultural practices. While the current situation points that consumption of the vegetables in the province poses limited health concerns due to organochlorine pesticides, the unmonitored use of products containing these compounds may result in elevated levels. Continued monitoring and a call for the South African legislature to revise its regulations of the Fertilizers Act to reflect the current international laws on pesticides management is recommended.

Chemical Contamination Pathways and the Food Safety Implications along the Various Stages of Food Production: A Review.

Historically, chemicals exceeding maximum allowable exposure levels have been disastrous to underdeveloped countries. The global food industry is primarily affected by toxic chemical substances because of natural and anthropogenic factors. Food safety is therefore threatened due to contamination by chemicals throughout the various stages of food production. Persistent Organic Pollutants (POPs) in the form of pesticides and other chemical substances such as Polychlorinated Biphenyls (PCBs) have a widely documented negative impact due to their long-lasting effect on the environment. This present review focuses on the chemical contamination pathways along the various stages of food production until the food reaches the consumer. The contamination of food can stem from various sources such as the agricultural sector and pollution from industrialized regions through the air, water, and soil. Therefore, it is imperative to control the application of chemicals during food packaging, the application of pesticides, and antibiotics in the food industry to prevent undesired residues on foodstuffs. Ultimately, the protection of consumers from food-related chemical toxicity depends on stringent efforts from regulatory authorities both in developed and underdeveloped nations.

Microbial levels on street foods and food preparation surfaces in Mangaung Metropolitan Municipality.

BACKGROUND: The street food sector has become an important component of the food distribution system in many cities in both developing and industrialised countries, particularly for midday meals. However, certain street food can pose a significant risk to consumers because of microbiological contamination. AIM: The aim of this study was to determine the microbial levels of street foods and preparation surfaces in Mangaung Metropolitan Municipality. SETTING: The study selected study setting was vending sites close to taxi ranks where prepared meals were accessible to consumers. METHODS: The study was conducted in Mangaung Metropolitan Municipality during the winter season. Samples were collected through convenience sampling from the representative towns Thaba Nchu, Botshabelo and Bloemfontein. Using swabs, surface samples were collected and quantified from selective media. Eight beef samples were also collected; the microbial load on each sample was quantified and identified using a RapID kit. RESULTS: The surface swabs obtained in Botshabelo (1.1 × 104 cfu/m2 - 1.1 × 106 cfu/m2) showed higher microbial counts as compared to those obtained in Bloemfontein (1.1 × 104 cfu/m2 - 1.1 × 105 cfu/m2) and Thaba Nchu (1.1 × 104 cfu/m2 - 1.1 × 105 cfu/m2). Higher microbial counts were observed on meat samples sampled in Thaba Nchu (50 cfu/g x 105 cfu/g), Bloemfontein (48 cfu/g x 104 cfu/g) and Botshabelo (33 cfu/g x 105 cfu/g) when compared to international microbiological standards. After assessing the microbial levels, Staphylococcus aureus, Escherichia coli, Candida guilliermondii, Corynebacterium jeikeium, Psychrobacter phenylpyruvicus and Peptostreptococcus tetradius were identified. CONCLUSION: This study confirmed contamination of surfaces and food served by vendors in Mangaung Metropolitan Municipality. The identified foodborne bacteria could pose a public health problem in each specific locality.

Identification of airborne microbiota in selected areas in a health-care setting in South Africa.

BACKGROUND: The role of bio-aerosols in the spread of disease and spoilage of food has been described in numerous studies; nevertheless this information at South African hospitals is limited. Attributable to their size, bio-aerosols may be suspended in the air for long periods placing patients at risk of infection and possibly settling on surfaces resulting in food contamination. The aim of the study is to assess the microbial composition of the air in the kitchen and selected wards at a typical district hospital in South Africa. Air samples were collected using the settle plates and an SAS Super 90 air sampler by impaction on agar. These microbial samples were quantified and identified using Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) and Analytic Profile Index (API). RESULTS: Microbial counts were found to be higher in the fourth (≤6.0 × 101 cfu/m(-3)) sampling rounds when compared to the first (≥2 cfu/m(-3)), second (≤3.0 × 101 cfu/m(-3)) and third (≤1.5 × 101 cfu/m(-3)) sampling rounds. Genera identified included Bacillus, Kocuria, Staphylococcus, Arthrobacter, Candida, Aureobasidium, Penicillium and Phoma amongst others. The presence of these pathogens is of concern, attributable to their ability to cause diseases in humans especially in those with suppressed host immunity defenses. Furthermore, fungal genera identified (e.g. Candida) in this study are also known to cause food spoilage and fungal infections in patients. CONCLUSION: Results from this study indicate the importance of air quality monitoring in health-care settings to prevent possible hospital-acquired infections and contamination of hospital surfaces including food contact surfaces by airborne contaminants.