Sodium Silicate Toxicity

Toxicity Classification

Sodium silicate is a corrosive substance and exposure to it is harmful. Toxic effects are hypothetical and based on exposure time and concentration. According to the Pesticides Action Network (PAN) Pesticides Database, it is not known if sodium silicate carries carcinogenesis potential. Because it is corrosive, it is possible to suffer from sodium silicate poisoning. Therefore, if exposure is chronic, it could be considered toxic. The effects vary considerably based on the amount an individual is exposed to. According to the International Programme on Chemical Safety, "there are no relevant toxicological analyses for this chemical."

As outlined by the International Programme on Chemical Safety, The routes of exposure can occur from ingestion, inhalation, and skin and eye exposure. Exposure to sodium silicate can occur through skin contact contact with strong binders and cements. Routes of exposure also include the esophagus and lungs. This occurs through inhalation of sodium silicate in its powdered form.

Two studies titled Patty's Industrial Hygiene and Toxicology by Clayton GD & Clayton FE,1993, tested toxicity of sodium silicate in animals. The first tested acute toxicity of sodium silicate on mice. The second tested the effects of chronic ingestion on dogs. In mice, "Acute oral toxicity LD50 to mice is 1280 mg/kg as a 10 percent solution. This produced mild skin irritation in the mice." In the study preformed on dogs, "Dogs were fed sodium silicate in their diet at a dose of 2.4 g/kg per day for four weeks...Polydipsia and polyuria were observed...Damage to renal tubules was observed." Polydipsia in dogs signified that kidney damage was a result of chronic exposure to sodium silicate.

In humans, the symptoms of sodium silicate exposure are known in cases of acute poisoning. These symptoms manifest in burns and pain at point of exposure. If inhaled, sodium silicate can burn the throat lining. Skin exposure results in burns. Toxicity in minute amounts, based on the results of experiments in dogs, could result in similar thirst and throat dryness in humans. No experiments on minute ingested exposure have been performed on humans.

According to the U.S. National Library of Medicine, sodium silicate is used in wastewater treatment. It is also used as "sealants, binders, deflocculants, emulsifiers, and buffers." Professions involved with piping and in the prevention of corrosion can also come into exposure with sodium silicate. Sodium silicate is also used as an insecticide and fungicide. Professions that come into contact or make use of these substances may also come into contact with sodium silicate. Individuals in these professions should take precautions not to inhale or ingest sodium silicate.