My sister-in-law Rebecca recently decided to replace all of her warped, missing-topped food storage containers. Having heard some of the rumblings about toxins leaching into food from microwaved plastic and other unpleasantness, she asked my advice for the safest (and most environmentally sound) brands to buy.

I was at a loss. I, too, have been concerned about the plastic my family is using, especially because a lot of my new-mom-friends have been trading scary news about unsafe baby bottles and toxic toddler spoons. I've stopped putting any of my daughter Sadie's plastic bottles, sippy cups and dishes in the microwave or the dishwasher, instead heating food on the stove or in a ceramic dish, and hand-washing everything.

But what I hadn't heard about was the solution. Time to do some research.

The environmental impact of using plastic are obvious and well-documented: plastic causes pollution, its manufacture consumes dwindling fossil fuels, and even plastic that gets recycled is taxing resources every step of the way.

But it's here to stay, even though most of us are hopefully doing our part where we can to use less plastic.

When it comes to using plastic to contain food and drinks, the news is even more troubling. Chemicals used to make plastic soft and flexible (such as the plastic wrap we use to wrap our leftovers) can leach into the foods it touches. Although there are conflicting studies on whether or not it causes health effects, some believe it is carcinogenic. Meanwhile, microwaveable containers, baby bottles and other items are made with plastic that contains a chemical called Bisphenol A, which, over time, can break down, again tainting food or liquid contained therein. The danger is that Bisphenol A is known to be a hormone disruptor and can stimulate levels of estrogen.

National Geographic's excellent Web site, The Green Guide outlines the best (and worst) plastics to use. In a nutshell, check the number on the bottom of a piece of plastic — it indicates what type it is. The best include numbers 4, 5 and 2, and the worst include numbers 3, 6 and 7.

The site also explains that "microwave-safe" simply means that the plastic container won't warp or melt in the microwave — it's not a guarantee that high heat won't leach chemicals into your food.

A quick check of my daughter's paraphenelia brought both good news and bad... her sippy cups, Snack Trap and plates all seemed to be made from #4 or #5 plastic, but her Avent baby bottles are on The Green Guide's Avoid list (although with further checking, I found that Avent claims it complies with an European Union ban on using phthalates). And I was interested to see that some plastic wraps and bags, such as those from Ziploc and Glad, were made of the "good" plastic, while others, such as Reynolds Wrap, are bad.

In the end, Rebecca went with a Rubbermaid set that passed the safe plastic test. But I'm guessing she'll think twice now before microwaving her leftovers in it.


Image courtesy iLoveButter.