Drinking water Technology, Eawag, developed a method by which hazard maps could be produced for geogenic toxic substances in groundwater. This provides an efficient way of determining which wells should be tested. Parameters for drinking water quality typically fall within three categories: Physical and chemical parameters include heavy metals, trace organic compounds, total suspended solids (TSS), and turbidity. Microbiological parameters include Coliform bacteria, "E. coli", and specific pathogenic species of bacteria (such as cholera-causing "Vibrio cholerae"), viruses, and protozoan parasites. Chemical parameters tend to pose more of a chronic health risk through buildup of heavy metals although some components like nitrates/nitrites and
Crop weed of 40–100% and accounts for around $7 billion in losses annually. Around 100 million hectares of land in Sub-Saharan Africa are affected by striga. Barnyard grass has been identified as a culprit in global rice yield losses and certain species have been known to mimic rice. Crop weed Crop weeds are weeds that grow amongst crops. Examples of crop weeds include chickweed, barnyard grass, dandelion, striga and fallopia japonica. Despite the potential for some crop weeds to be used as a food source, many can also prove harmful to crops, both directly and indirectly. Crop weeds can inhibit the growth