Is polyacrylamide toxic to humans?

Polyacrylamide itself is non-toxic because when it enters the human body, most of it will be excreted out of the body within a short period of time and will not be absorbed by the digestive tract. Most products containing polyacrylamide will not irritate the skin. Only some water-disintegrating products may have residual alkali. Repeated long-term exposure will irritate the skin but will not cause harm.

 However, acrylamide is the monomer used in the synthesis of polyacrylamide, and in its case, it is toxic. Acrylamide is a neurotoxic agent that can cause damage to the nervous system, superficial movement disorders, muscle weakness and other symptoms of poisoning. Therefore, the health departments of various countries stipulate that the residual amount of acrylamide in polyacrylamide industrial products is generally 0.5% ≤ 0.05%. When used for the purification and treatment of industrial and urban sewage, the content of acrylamide generally does not exceed 0.2%; when used for the treatment of direct drinking water, the content of acrylamide should be less than 0.05%.

Polyacrylamide is non-toxic and has the following three properties:

1. Flocculation. Polyacrylamide can flocculate suspended solids through electrical neutralization.

2. Adhesion. It can be combined through physical and chemical effects.

3. Thickener. It thickens under both neutral and acidic conditions, but when the pH value is greater than 10:00, it is easily hydrolyzed. Its working principle is:

1. Principle of flocculation: When polyacrylamide is used for flocculation, it is related to the surface properties of the flocculant. The dynamic potential on the particle surface is the reason why polyacrylamide with opposite surface charge adds surface charge, thereby reducing the dynamic potential and cohesion.

2. Surface adsorption: various adsorptions of polar group particles on polyacrylamide molecules.

3. Reinforcement: The polyacrylamide molecular chain and dispersed phase connect the dispersed phase together to form a network through various mechanical, physical, chemical and other functions.