A Consumer Council test on dry pet food has detected harmful substances in some of these products.
Although they are unlikely to pose immediate health concern because of the relatively low amount detected, pet owners tasked with the choice of food for their pets are rightly worrisome.
The test, on 39 dry pet foods comprising 20 dog foods and 19 cat foods, revealed the presence of the carcinogen aflatoxin B1, and the contaminants, melamine and cyanuric acid, in some of the samples.
Trace amount of aflatoxin B1, ranging from 1.0 to 2.0 µg/kg dry pet food, was found in 7 models - 4 dog foods and 3 cat foods.
Aflatoxins are produced by various species of a group of toxin-producing fungus found on crops. Among the aflatoxins (B1, B2, G1 and G2), aflatoxin B1 is most commonly found in crops, and is the most toxic and carcinogenic. Exposure to aflatoxin B1 may cause liver damage and cirrhosis in animals.
The consolation (if any) is: the levels of aflatoxin B1 found in the samples are all within the safety limits established by the European Union Commission Regulation (EU) No. 574/2011.
The EU sets the maximum amount of aflatoxin B1 in animal feeds (with a moisture content of 12%) at 0.01 ppm (10 µg/kg) in complementary and complete feed, and at 0.02 ppm (20 µg/kg) in feed materials (when animals are given a diet consisting of various feed materials).
The U.S. Food and Drug Administration (FDA) also sets action level for the regulation of aflatoxins content in animal feeds and feeding ingredients.
Veterinarians are generally of the opinion that the low amounts of aflatoxin B1 detected in the test samples are unlikely to cause a health risk to pets for short-term consumption.
However, they caution that since aflatoxin B1 is a known carcinogen, it should best be avoided; long-term exposure to aflatoxin B1 could increase the risk of liver impairment, tumors in liver, and suppressed immune system.
The level of risk depends on the species, age of animal, health condition, doses and duration of aflatoxin exposure. Young animals, and pets in pregnancy, are usually more sensitive to aflatoxin.
Pets with symptoms such as lethargy, weakness, loss of appetite, vomiting, bloody diarrhea should be brought to the vet for medical attention.
Besides the detection of aflatoxin B1, 2 models were found with the contaminant melamine and 2 others with cyanuric acid, both in only small quantities.
Melamine and melamine-related compounds such as cyanuric acid were at the centre of a widespread outbreak of renal failure and deaths of cats and dogs in 2007 when some pet food products were found with the contaminants. It was suspected that such harmful substances were added to pet food ingredients to increase the apparent protein levels of the products.
The Codex Alimentarius Commission, the USFDA and the EU Regulation all adopted the maximum melamine level to be limited at 2.5 mg/kg for animal feeds. All samples in the test were found to be in compliance with the requirement.
In the opinion of veterinarians, the detected amounts of melamine and cyanuric acid are of a very low level and since the two contaminants exist individually in the samples, and are not in co-existence, there is no cause for undue concern over the health risk they pose to pets.
The danger arises when both contaminants, though individually of a low acute toxicity, are taken in combination which is far more toxic than either compound alone.
Exposure to both substances may lead to formation of crystals, resulting in blockage of tubules in kidneys that may cause acute renal failure in animals.
Care should be taken if mixing different brands of dry food in order to avoid the hazard of feeding both contaminants to your pets.
Unbeknown to probably many pet owners is the availability of information regarding daily feeding instruction on all pet-food labels. Owing to the varied nutritional contents per gram of different products, the daily feed amount differs also from brand to brand.
As such, when changing brand, consumers are advised to read the daily feeding instruction so as not to over-or under-feed your pets.
All samples were found to be free of Salmonella and E. Coli O157. These are pathogens harmful also to humans.
Some useful tips for pet lovers:
- Read the ingredient list and "used by" date before purchase. Buy the right amount, do not buy in big bulk. Store pet food properly in its original package inside an air-tight container - not in humid environment and in the event the food deteriorates and smells, it should be discarded.
- And always clean the food tray to keep the food clean.
- Feed your pets with reference to the daily feed instructions. Consume pet food as soon as possible after opening the package.
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- 2014.04.15