"Toxic is as toxic does." Here's exactly what Wikipedia has to say:

Boric acid, sodium borate, and sodium perborate are estimated to have a fatal dose from 0.1 to 0.5g/kg.[5] These substances are toxic to all cells, and have a slow excretion rate through the kidneys. Kidney toxicity is the greatest, with liver fatty degeneration, cerebral edema, and gastroenteritis. Boric acid solutions used as an eye wash or on abraded skin are known to be especially toxic to infants, especially after repeated use due to its slow elimination rate.

Example: a 40-lb child is 18.1 kg, which means a fatal dose of borax would be between 1.81 and 9.5 g. That means that child would have to consume about a half-teaspoon to two teaspoons of straight, non-dilute borax, assuming a kid would eat something that nasty-tasting (keeping in mind that as nasty as it is, kids are weird). Of course, you don't keep household cleaners--any household cleaners, including baking soda--where your kid could reach them, right? RIGHT? And it would take a lot less, say, bleach, to severely injure or kill a child that size with a lot greater harm to the environment in general.

If you go to PesticideInfo.org, you'll see that borax is considered neither acutely toxic nor a likely carcinogen. That website is run by the Pesticide Action Network North America, which keeps an exhaustive database of environmental toxins.

Bottom line: Borax is a problem if you repeatedly expose someone, especially small someones, *directly* to it, usually as a strong solution applied to the skin or eyes. Otherwise, washing dishes and clothes with it is not a big deal; it rinses away and doesn't compromise the environment.

Lynn Siprelle, Editor