While biocides can have severe effects on human health and/or the environment, their benefits should not be overlooked. To provide some examples, without the above-mentioned rodenticides, crops and food stocks might be seriously affected by rodent activity, or diseases like Leptospirosis might be spread more easily, since rodents can be a vector for diseases. It is difficult to imagine hospitals, food industry premises without using disinfectants or using untreated wood for telephone poles. Another example of benefit is the fuel saving of antifouling substances applied to ships to prevent the buildup of biofilm and subsequent fouling organisms on the hulls which increase the drag during navigation.