Admixture health & safety
All the principal admixture companies supply safety data sheets for their products. These should be carefully checked and advice on handling passed to those working with the products.
Most admixtures are water-based and are non-hazardous or, at worst, irritants. A small group have a high pH and are therefore harmful: this particularly applies to some air-entrainers, water-resisting admixtures and sprayed concrete accelerators. A few, mainly accelerators and corrosion inhibitors, may be toxic.
Some organic admixtures have a high oxygen demand under biological breakdown which, during disposal or in the event of a major spillage, may cause hazards for fish in rivers and in processing effluent in water treatment plants. Any such problem should therefore be notified to the appropriate authorities as soon as it happens.