There's so many tidbits that make up our modern lives, it's easy to overlook some environmental nasties right under our noses.

For example, lead wheel balancing weights. These are small strips of lead that are crimped on to the tire rim; often added when getting our car's wheels aligned and balanced.

I'd never really given them much thought until learning that they account for the largest new lead releases into the environment according to the Center for Environmental Health.

It's estimated an incredible 65,000 tons of lead wheel weights are in use in the USA, and around 3% of wheel weights become dislodged; winding up on the road where other vehicles continually run over them until they dissipate and are washed or blown away. That 3% translates to 1950 tons - that's a lot of lead. Lead is one of those substances where a little bit goes a long way in terms of detrimental environmental effects - it's a very potent, bioaccumulative toxin.

Lead wheel weights have been banned in the European Union since the middle of 2005. Japan and Korea are in the process of phasing them out. I'm not sure where Australia is on the issue, but I think we still allow them.

In the USA, the EPA has refused to enact a ban, opting for voluntary industry action.

Some US states have introduced their own bans and last week, the Center for Environmental Health (CEH) struck a deal with Chrysler and several companies manufacturing wheel balancing weights, requiring the companies to end the use of them in California by the end of 2009. According to the CEH, this will stop 500,000 pounds of lead entering into the environment in California each year.

Read more on the landmark agreement here.

Hmmm... makes me wonder how much lead fishing sinkers contribute annually. Back when I used to fish a lot, I'd lose pounds of the darned things each year - again, it's just something I never gave much thought to in those days.