Antibiotic of the week: Sulfadimidine or Sulfamethazine

Antibiotic Pollution Index: 296 (12 October 2017)
What is the Antibiotic Pollution Index?

What it does
This drug blocks the propagation of bacteria, by interfering with folic acid synthesis. Folic acid is important for a number of processes, one of which is building up DNA. It is a broad spectrum, synthetic antibacterial drug.

Who gets it
Sulfadimidine or Sulfamethazine (both refer to the same antibiotic) is often fed to or mixed in drinking water of pigs, cattle, poultry and fish, to prevent disease in crowded farms and fisheries. This drug is also used as a growth promotor in the meat production. However, for sulfadimidine, no lab-based evidence for growth promotion has been found, with the exception of one organ: the thyroid gland. This gland produces a hormone that regulates growth. But a bigger gland does not necessarily lead to a hormone boost. In fact, pigs and rats that get high sulfadimidine dosages are more lean. Even worse, enlargement of the thyroid gland has been described as an oncogenic effect of the drug. In earlier days, sulfadimidine was also approved for medical use, but this has been discontinued in most countries.

Where may it be produced?
US, China, Czech Republic, the Netherlands, Poland.

And, SquaredAnt, does it pollute?
Sulfadimidine or Sulfamethazine is produced in enormous amounts: in China, one factory alone claims a production capacity of 1000 metric tons a month. This would yearly amount to ~12% of the lower estimate of the annual worldwide use of all antibiotics combined (100.000-200.000 metric tons). Pollution has been observed in China, Thailand, Canada and the US, with highest concentrations in agriculture soil and agriculture waste water.

Warning lights
Sulfadimidine pollution has not only sparked antibiotic resistance, but even more so, some bacteria have adopted this antibiotic as a nutrient source. In soy crop fields in Canada, where high dosages of sulfadimidine were put into the soil to study the effect of antibiotic residue in fertilizer, a microbacterium bacteria species started to use sulfadimidine as a carbon source. Translated to humans: they got shot at, warded off the bullets, and built a steel mill with it. We created a monster…. today in your fields, tomorrow in your guts.

Any common sense in this antibiotic?
Concerns related to sulfadimidine use in agriculture have already been raised many years ago. Reasons were potential health risks and the high number of non-compliant farms. In 1989, sulfadimidine was almost withdrawn from the US industry. The New York Times News Service reported that “The long regulatory history of sulfamethazine is the latest illustration of the difficulty federal agencies are having in untangling the web of scientific, political and economic issues before toxic substances can be eliminated from the food supply.” The withdrawal never took place. Non-compliance and conflicts of interests continue until today, throughout the world. Common sense is hard to find.



Leave a Reply

Your email address will not be published. Required fields are marked *