Stellenbosch University scientists are using sophisticated molecular analysis to find out if the levels of harmful bacteria on locally grown fruit and vegetables, is linked to contaminated river water used for irrigating crops.
The research is important because it is likely to increase pressure on local municipalities to improve their water-treatment management. Fruit- and vegetable-growing businesses risk losing key customers if there are unacceptably high levels of dangerous bacteria on their crops, but had limited scope to clean up the water they obtained from local rivers since setting up their own water treatment plants would be impractical and unaffordable, said Jo Barnes, an epidemiologist from the university’s community health department.
Most of the dangerous bugs came from improperly treated sewage discharged into rivers by municipalities, but a small amount came directly from communities living along river banks, she said.
Barnes’ research into river contamination in Western Cape has already shown that the water contains [...] E coli, salmonella, listeria, adenovirus, and several strains of streptococcal bacteria. [L]evels of E coli were thousands of times higher than SA’s recommended safety levels of 2000 bacteria per 100ml of water, a threshold that is already twice that of the European Union.
Since cooking destroys most bacteria and viruses, the researchers are focusing on food eaten raw or lightly cooked. Barnes said anxious consumers could reduce their risk of infection by rinsing fruit and vegetables in a bowl of water containing a bit of household bleach.
Source: Tamar Kahn, Business Day (Johannesburg) / allAfrica.com, 18 Aug 2008