Health risks from irrigating crops and watering livestock when toxic cyanobacteria blooms are present

Cyanobacteria blooms can occur in water sources used for irrigation and watering stock and toxins may present a risk to food crops and livestock. This frequently occurs when effluent from wastewater treatment is stored for long periods in open lagoons. Recent work has demonstrated the uptake of toxin and bioaccumulation into some food crops.  There are a number of factors influencing the potential for uptake including bioavailability of the toxin and the crop type and it is not clear whether toxin uptake applies to all food crops commonly irrigated.   Further, most experimental studies have used short term irrigation periods and toxin levels that are not as high as reported in recycled water lagoons.

It is important to understand the risk to agriculture through repeated irrigation of crops with water containing toxins to inform the human health risk assessment.  However, the risk to agricultural end users are not well understood.  For example, what are the risks to consumers of food grown with water containing toxins and can the toxin be detected in foods and does it bioaccumulate. Also is there any risk to stock from drinking water with toxins or feed on crops and pasture irrigated with toxins or to humans that come in contact with irrigated crops.

The projects seeks to understand the human and livestock risks when water containing cyanobacteria toxins are used for irrigation and watering. This is to include all toxin risks that are likely to occur from cyanobacteria occurring in recycled water and fresh surface waters in Australia.