Organically grown food is more nutritious than chemically fertilised food

Not necessarily. The nutrient content of foods can vary greatly depending on factors such as variety, soil, type and amount of fertiliser (organic or chemical), amount and intensity of sunlight, season, method of storage and so on. Irrespective of the type of fertiliser applied, plants utilise the nutrients from both types of fertilisers in the same way. The difference in growth and nutrient content of the food will depend on the amount and type of nutrient available and the balance between the nutrients in the fertiliser and the soil. Generally, any nutritional difference between organically fertilised food and chemically fertilised food is unlikely to be significant.

However, impurities present in fertilisers can find their way into the food chain. Recent surveys of residues of Australian foods have found relatively high levels of the heavy metal cadmium. In some instances, most notably potatoes, the level exceeded the maximum permitted level allowed by regulatory authorities. The origin of the cadmium was traced to the super-phosphate used on the crops.