Chlorate & Perchlorate
Chlorate
Chlorates are strong oxidants with herbicidal and biocidal activity. Since 2008, chlorate is no longer authorised for use as a pesticide in the European Union. Also, sodium chlorate may no longer be used in biocide products. Still more than 10% of the food samples tested by European Food Safety Authority in 2015 contained chlorate residues higher than 0.01mg/Kg, which the highest levels found in leafy and fruiting vegetables with higher levels being found in the frozen produce rather than the respective fresh produce.
Food can be contaminated in many ways during production including the use of chlorinated water used in irrigation, washing of the produce as well as from disinfection and cleaning of food preparation surfaces and tools.
The current MRL for chlorate is a default 0.01mg/Kg and is regulated under Reg EU 396/2005. RPS can provide rapid analysis of chlorate residues by UHPLC-MS/MS down to 0.01mg/Kg in food and water.
Perchlorate
Perchlorate is a potential carcinogen and it has been shown to interfere with the iodide uptake in the thyroid gland limiting the ability to produce thyroid hormones. Recent studies indicate developmental growth effects at low concentrations, particularly to the development of the nervous system.
Perchlorate is very stable in water and its salts are also highly soluble in water which make it highly mobile. It occurs naturally in deposits of Nitrate and Potash and is released as an environmental contaminant using nitrate fertilisers and from the manufacture use and disposal of ammonium perchlorate used in rocket propellants, fireworks, explosives and other industrial processes. Perchlorate can also be formed from the degradation of sodium hypochlorite used in water treatment. Perchlorate enters the food chain primarily form water soil and fertilizer used to grow crops.
Commission Recommendation EU No. 2015/682 was adopted in 2016 following a review of the levels found in food from monitoring in the European Union. Harmonised intra-Union trade reference values have been published for unprocessed food and include:
- Foods for infants and young children - 0.02 mg/Kg
- Herbs and salad plants – 1 mg/Kg
- Fruits and vegetables – 0.1 mg/Kg
- Other foods – 0.05 mg/Kg
Dried, diluted, processed and compound foodstuffs will be regulated under Article 2 of Regulation (EC) 1881/2006 which is currently being amended for enforcement in January 2020.
