Plastic Safety

Caroline Baier-Anderson
Health Scientist for the Environmental Defense Fund
Tuesday, April 22, 2008; 11:00 AM

The National Toxicology Program acknowledged in a draft report that Bisphenol A, a chemical which can be found in thousands of everyday plastic products like baby bottles and compact discs, may cause breast cancer, early puberty development and prostate cancer. Phthalates, a chemical known for prolonging the life span of plastic products, has been banned in the manufacturing of toys in most European countries.

Caroline Baier-Anderson discusses, a health scientist and an assistant professor in the Department of Epidemiology and Preventive Medicine at the University of Maryland, Baltimore, was online Tuesday, April 22, at 11 a.m. ET to discuss protecting your health against plastic products ladened with harmful chemicals.

Submit your questions and comments before or during today's discussion.


Caroline (Cal) Baier-Anderson: Good Morning! I am happy to be here to chat about plastics and health.

There are lots of reasons to reduce our use of plastics: to decrease our reliance on petroleum, to minmize waste generation (overall, we have a poor track record on recycling), and of course, the chemicals used to make plastics come with risks to human health and the environment. What are your thoughts and concerns?


Philadelphia: I'm not sure what to make of all the news about plastics -- it seems as if they have been around for a long time with few obvious health consequences. But the microwave introduces another whole set of possible problems. Would I be wise NOT to microwave plastics?

Caroline (Cal) Baier-Anderson: With regards to the supposed safety of plastics, I must say that no one has ever really looked!

There are no large scale case-control epidemiological studies (the "gold standard") investigating linkages between chemicals in plastics and health effects. The industry cannot assert that there is a 50-year safety track record without actually doing the studies.

As for microwaving - it is best not to microwave plastics, particularly since alternatives are widely available.


Arlington, Mass.: Have there been any studies comparing BPA levels in children who were breast-fed with those who were bottle-fed? Does this chemical persist and accumulate in the body? Thanks!

Caroline (Cal) Baier-Anderson: There have been several studies measuring the levels of BPA in human milk. To my knowledge, there have been no published studies following children exposed through milk or formula (liquid formula could contain small amounts of BPA from the can linings).

BPA is not considered to be persitent and bioaccumulative. But the use of polycarbonate plastics made with BPA is so common that exposures are near constant.


Washington, DC: From some of my reading I understood that babies were exposed to more BPA through the formula cans than through the bottles. Is there any move to remove BPA from the cans of baby formula?

Caroline (Cal) Baier-Anderson: Nalgene, the company that makes polycarbonate bottles, has recently announced that it will stop making these bottles and Wal-Mart has announced that it will be phasing out baby bottles made with BPA. In other words, manufacturers and retailers are responding to new scientific data linking BPA with health concerns.

I would not be surprised if manufactures are actively looking at alternatives to BPA in response to market pressure, but I have no "inside knowledge" as to what they may be doing.

In the meantime, consumers who might be concerned about BPA in cans of baby formula can purchase powdered forumla mix.


Boston: Are "Nalgene" and other polycarbonate water bottles safe for adult males?

Caroline (Cal) Baier-Anderson: We don't really know the answer to this important question. While some studies using laboratory animals suggest that fetal or early developmental exposure to BPA (used to make polycarbonate) could increase the risk of prostate cancer, there are no studies looking at adult exposures.

Given this uncertainty - my view is that it is wise to reduce exposures.


Laurel, Md.: Where can I find a complete list of all the products containing BPA?

Caroline (Cal) Baier-Anderson: Great question! The problem is, such a list does not exist!

Under the (broken) laws that govern chemicals managment in the US, there is no requirement for chemical manufactures to know or collect information on how buyers are using the chemicals. Manufactures purchasing chemicals to make stuff rarely have to reveal what chemicals that they are using.

Labeling requirements vary by product (cosmetics, furniture, coffee makers, etc.), and many product "recipes" are actually secret! As a result, most retailers don't know what chemicals are in the products they sell on their shelves - and neither do we.


Richmond, Va.: How do I know whether BPA, for example, is in the plastics I buy when the items are not labeled? If the retailers are trying to get manufacturers to not use these chemicals, do you know if the retailers intend to label their products as BPA free?

Caroline (Cal) Baier-Anderson: See previous answer for the first question.

Note that some companies are advertising the absence of BPA.


Raleigh, N.C.: I have two young children, and I would like to know what I should replace first -- shampoo and bath stuff, what they're eating/drinking from, what we store food in, etc. We don't have endless cash (especially now with food prices and gas soaring) and if I need to choose one or two things to eliminate, which should they be?

Caroline (Cal) Baier-Anderson: This is always a tough question, because many (but certainly not all) of the products "without" the known "chemicals of concern" seem to cost more.

There is no "scientific" answer to this question. We have no idea which products result in the greatest exposure. As individuals we make the best decisions we can. The point that I tried to make in the article on plastics is that it is simply not fair that consumers need to make these decisions. We should be asking the government to do a better job making sure these chemicals - particularly the chemicals used in every day products - are thoroughly tested BEFORE they wind up on our shelves (and in our bodies!)


Washington, DC: Should I purchase my milk in half-gallon paper containers, rather than the plastic one gallon jugs or do the coatings on the paper containers pose risks as well?

Caroline (Cal) Baier-Anderson: Plastic milk jugs are made from high density polyethylene (HDPE), labeled with a 2 in a triangle.

HDPE is considered to be one of the safer alternatives, but it is still recommended that you recycle this plastic, and not re-use it.


Washington, DC: What's a better choice for food storage: plastic wrap, aluminum foil, or ziploc or regular baggies? Thanks.

Caroline (Cal) Baier-Anderson: How about wax paper? Wax paper storage bags are available on several "green products" web sites.


Washington, DC: I've tossed most of our plastic storage items, and replaced it with pyrex pieces over the weekend. But now I'm wondering about those plastic tops for the pyrex. Do you have a view as to whether these are safe for food storage? Thanks.

Caroline (Cal) Baier-Anderson: Interesting question. In theory, microwaveable plastic as been tested for safety, but given that the scientific data on the health effects of these chemicals is a moving target, it is better not to microwave plastic.

Have you considered putting a microwaveable glass plate on top of the pyrex as a splash guard?


Brunswick, Md: If the Consumer Product Safety Commission has studied and shown that pthalates are safe, why should I as a busy working mom start worrying now about a component in plastic that has been in use for decades?

Caroline (Cal) Baier-Anderson: I covered part of this question in an earlier post. What I would like to emphasize here is that most of the science regarding health concerns is new.

Why? Because the EPA does not require robust testing for chemicals used in commerce. we don't know much about most of the chemicals that are used to make products that we use every day. Advances in our understanding of harmful effects moves slowly, because it does not receive the funding it requires to make it a priority, and testing is largely in the hands of the industries that manufacture or use the chemicals.

The laws governing how chemicals are assessed are broken. They need to be fixed, so that testing is done before the chemicals are used in everyday products. Consumers should not have to make these decisions.


Brunswick, Md: If these chemicals are banned from use, what will replace them? Isn't that a scarier question -- using untested alternatives??

Caroline (Cal) Baier-Anderson: Good point. But this also gets to my last response - that the laws governing chemical assessment must be fixed.

We need robust testing of chemicals before they are used in commerce. We should not be replacing known "bad actor chemicals" with unknowns! The chemicals should be vetted before they are used as replacements.


Washington, DC: I struggle with trying to reduce the amount of trash in my child's lunch box, and used to use Glad "disposable" tupperware that I could wash (in the dishwasher) and reuse. Now I am concerned that this strategy has exposed her to more BPA, etc, and that I'd be better off using single-use disposable baggies that might leach less because they haven't been washed in high heat. Any advice for how I can pack foods in safe but environmentally conscious ways? (She is very young so pyrex is not an option.)Thanks.

Caroline (Cal) Baier-Anderson: First off, some plastics are better than others - check the triangle with the number: 1,2, 4 and 5 are better choices.

Wax paper "baggies" are available online through different distributors. Aluminum foil can be used and recycled.

(It is not too hard to train kids to bring these containers and used foils home...they started to resist around middle school, but somehow we got through it)


Anonymous: I really appreciated this article. Ever since I got sick in the workplace from mold contamination, I have been reacting to scented products, which cause in me bronchial inflammation and asthma. Am I reacting to the phthalates? Why are these placed in scented products? Since phthalates can trigger asthma, why are they allowed by the FDA?

Caroline (Cal) Baier-Anderson: In general terms, the way that our regulatory system has developed, the standard of proof required to trigger regulatory action is ridiculously high.

Chemicals are considered to be "innocent until proven guilty", and public health protection suffers as a result.

I am sorry, I do not know if you are reacting to phthalates, or something else your environment.


Arlington, Va: Stonyfield baby yogurts are packed in Recycling code 6 containers, that means these containers contain BPA, and strangely the yogurt for adult is packed in Recycling code 5 containers which according to the articles in this newspaper is considered safe. Gerber baby food is packed in plastic containers marked with Recycling code 7, which is considered the unsafest. So have we been unknowingly feeding our little ones miniscule amounts of harmful chemicals all this while???

Caroline (Cal) Baier-Anderson: BPA is # 7, NOT 6. Interestingly, 6 is polystyrene, which is also on the list of plastics to avoid.

I do not know if the polysturene is leaching into the yogurt, but it might be worthwhile to send a letter to Stonyfield farms asking them to use #5, which is polypropylene, one of the "preferred" plastic materials.


replacing plastic cups and water bottles?: Should I replace my kids' plastic cups with stainless steel bottles? Those seem to have plastic tops as well . . . Thanks!

Caroline (Cal) Baier-Anderson: There is a lot of interest in this question of replacement.

The problem is that we don't have enough scientific data to determine what products are associated with the greatest exposures, so prioritization is hard to do.

I think we need to think about minimizing exposure - making changes that make sense to us, but then asking the government to do a better job of making sure that the chemicals used in these products have been thoroughly tested and we have a reasonable assurance of safety.


NEDC: How do I know when my nalgene bottles have begun to deteriorate? I hate to get rid of perfectly good plastic bottles that have already leached most of their BPA. That just means more stuff in the landfill.

Caroline (Cal) Baier-Anderson: Yes! Especially since they cannot be recycled!

Obvious scratches or discolortion make it easy. But it is possible that this process begins before we see it.

I have purchased a couple of non-BPA bottles and slowly (one by one) eliminated all of my plastic ones.


Washington, DC: I use a one quart Nalgene bottle at work and try to drink 2-3 quarts of water daily. It's not practical for me to use a little cup and continually schlep across the office to refill it and non-BPA bottles are not on store shelves yet. Does the positive effects of drinking lots of water outweigh the negative effects of drinking from a BPA bottle?

(A broader question is if one unintended consequence is that everybody throws away their big water bottles and ends up drinking more soda, juice, etc?)

Caroline (Cal) Baier-Anderson: I still don't see this as an "either/or" problem. I use a large glass while at work. And there are ceramic-coated aluminum water bottle alternatives (and others), so turning to sodas or even juices does not have to be the result.

As far as the cost/benefit of drinking water - to the best of my knowledge, no one has done this study.


Bethesda, Md.: I had read somewhere that some of these same chemicals are in IV tubes in the U.S. but is banned from being used in IV tubes in Europe. Is that true?

Caroline (Cal) Baier-Anderson: I think you are referring to IV tubes that use DEHP, a phthalate ester, as a softener. Since DEHP (or phthalates in general) can readily leach out of the plastic, several studies documented exposures in hospital patients who had IV tubes inserted.

Many hospitals have stopped using plastics made with DEHP, even here in the US. For more on this, check with Healthcare Without Harm, an organization that has worked very hard on this issue.


Potomac, Md 20854: I am really concerned about the CPVC water (hot as well as cold) pipes used in my whole house plumbing (instead of copper pipes). Other plastic containers can be avoided, but nothing can be done about the CPVC pipes. Is there some evidence of BPA or any other harmful chemical in the CPVC pipes?

Is there a way to filter out these harmful chemicals? We do use regular water filter built in our GE referigerator for drinking water. Thanks.

A.B. Singh -

Caroline (Cal) Baier-Anderson: Questions regarding water filtration are difficult to answer. There are many different ways to filter drinking water, and I would recommend that you speak directly with the manufacturer of the filter system to address specific concerns.


Washington, DC: I've managed to toss lots of our plastic food storage items, but I'd like to keep our Brita filter and pitcher. Do you have views as to whether that is a reasonable choice? Should I take care to only fill and use the water from the pitcher immediately after it drains through the filter, rather than let the water sit in the pitcher all day, or is that not necessary? Thanks.

Caroline (Cal) Baier-Anderson: This is similar to the previous question - please see the answer to that question.

But I would like to note that there is a whole industry devoted to evaluating what might leach out of all of the parts and pieces that comprise water systems, including water filters. Some components of water filters are indeed made of polycarbonate. There may be other rubber-like gaskets and widgets, and all parts must be evaluated.

It is best to go straight to the manufacturer of the filter to get the lowdownon these questions.


Industry Reasoning?: When people in the industry make comments that the studies showing BPA to be harmful are "flimsy," what exactly are their reasons? How are they backing up that assertion? Without knowing much about the studies and how they were performed, it's hard for the consumer to draw their own conclusions.

Caroline (Cal) Baier-Anderson: In the case of BPA, studies sponsored by, or paid by industry are largely negative - meaning that they identified no "significant" adverse health outcomes. Studies conducted by scientists from university laboratories were much more likely to identify signficant effects.

My view: Some of this has to do with the fact that most industry studies are older, so certain important factors may not have been taken into account (such as the chemicals in the rat/mouse food can block the activity of BPA). Academic scientist are also breaking new ground, looking at new and different (but important) biological changes.


Columbia, Md: Is the plastic in the TV dinners safe (specifically Lean Cuisine)?

Caroline (Cal) Baier-Anderson: Several questions have come through about frozen food containers - although some plastics have been approved for use in the microwave, for those who are concerned about it, when you can - pop the frozen food out onto a microwaveable plate. You can also cover it with another plate if you think that cooking it might splatter.

BUT I will say that although I do this when at home, I don't worry about it if it is not feasible or convenient. Stressing about it is also counterproductive!


Bowie, Md.: A lot of drip coffee makers are made of some sort of plastic. Do you know what type of plastic? Since high heat and plastic is not a good combination should we convert to the old percolators.

Caroline (Cal) Baier-Anderson: I do not know what type of plastic, but this is a good question!

Since this information is almost never readily available (see my previous rant on the unknown chemicals in consumer products) this might be worth a call to the manufacturer.

In the absence of regulatory action - this is our best option...let manufacturers (and retailers) know that we are concerned, and we want answers!


NYC: Hi, I am sitting in my office looking at a plastic bottle of water from Poland Spring. It is not identified as to its plastic type. At least where I can find it. It is a soft plastic. So my question is this: what does someone do regarding identification if the manufacturer is being obtuse?

I wonder how much Bisphenol A is contributing to the fact todays girls are entering puberty by the age of 10.

Caroline (Cal) Baier-Anderson: Hmm. There should be a label on the bottle. Most water bottles are #1 - ok for single use, then recycle.

I do think that letting manufacturers know we are interested and concerned will actually help move the debate forward. SO give them a call, send an e-mail, write a letter! And CC your congress person!

There have been a few small studies on BPA and puberty. It is an interesting question, but why is the government allowing these exposures while the scientists figure this out? Cart before the horse?


Bethesda, Md.: I wanted to bring up that I discovered recently that (at least according to some companies) #7 plastic does not always contain BPA. From my understanding #7 plastic is a "catchall" and you don't know for sure what it contains. I contacted Gerber about their Organic baby food (which is packaged in #7 plastic) and they told me it was actually a #1 interior and a #6 exterior and therefore was labeled #7. It does not contain BPA. You also can't recycle it, which is another issue. Does this sound accurate to you? This whole issue is incredibly frustrating for concerned parents.

Caroline (Cal) Baier-Anderson: Yes - it is a catch all. But we should not have to guess. The labeling should be clear and consistent. This makes me frustrated (and angry) too!


Concerned in Bel Air: Hi unfortunately I used both canned formula & bottles that were since found to contain bpa for my now nearly 5-year-old daughter. What should I do now (aside from already changing from plastic food storage containers to glass, wooden spoons for cooking instead of plastic, etc.)? Are there tests I should ask our pediatrician about for my daughter? Thank you.

Caroline (Cal) Baier-Anderson: Hi There -

One point I would like to emphasize is that when we talk about risk, we are not in any way, shape, or form, indicating that if you are exposed, you will have some health effect.

What we are saying is that there appears to be an association between laboratory animal exposure and certain biological changes that may translate into some human health risk. And from my perspective, we should be erring on the side of safety to protect public health, and decrease our exposures.

Since we do not know which exposures are most important (not studied - no data) it is really hard to judge the impact of eliminating certain uses. Therefore as individuals we do the best we can (please don't stress!) but we also ask the governmen, manufacturers and retailers to do more.


Kensington, Md.: It's hard not to get completely depressed about an issue over which it can be hard to exert much control. Obviously I can keep certain plastic products out of the house...but plastic is ubiquitous! It is everywhere! I feel responsible for keeping my daughter safe, but unarmed with the knowledge and tools to do so...and as you yourself admit, there really isn't even accurate info out there to find if one goes looking.

We should all realize the cost to our safety and health when corporations go unregulated in our aggressively capitalistic society. We can pay ourselves stimulus checks and build huge bombers, but we can't keep dangerous chemicals out of infant formula! Family values, indeed!

Caroline (Cal) Baier-Anderson: Thank you for sharing your thoughts! Very nicely said!


Damascus, Md.: I read in the Wall Street Journal this morning that Israel banned phthalates but later changed their mind and rescinded the ban? Are they crazy or do they have info to back up their decision?

Caroline (Cal) Baier-Anderson: One reason that regulators may be reluctant to regulate is the concern of being sued. This can result in pushing the bar to "demonstrate harm" higher and higher. Regulators may feel that they need to be armed with "evidence" that is lawsuit-proof. Even in the end, if the government loses the lawsuit, the cost to litigate, and the delays in actually regulating, are very high.

My view - the laws must be changed so that manufacturers and producers must provide sufficient scientific data to reasonably demonstrate safety. While we cannot prove a negative, we should be able to define how much, and what kind of data this would require.


Arlington, VA: I have a question that I want to pose delicately, because I realize that the plastic toxicity issue is a valid concern -- but why does the media, and the public, latch onto these less significant cancer factors when the biggest factors are diet, smoking, and exercise.

Is it because it is easier to blame a big corporation than to blame yourself? Is it because it is easier to throw away some plastic bottles than to change your lifestyle? What do you think about this?

Caroline (Cal) Baier-Anderson: It is always interesting to look at what "the media" is covering, but I do think there is more diversity in terms of coverage out there - you just need to look for it. (Thanks to the internet!)

With regards to smoking, obesity, diet and exercise, note that on today's front page is an article on decreasing life expectancy in some parts of the country, which is likely to be linked to these "life style" issues. Having said this - there have been a couple of lab animal studies evaluating the ability of chemicals, like BPA, to increase risk of diabetes by altering how the body handles glucose (sugar). The plot thickens...


Cambridgeshire, England, U.K.: With the significant increase in the number of children diagnosed with autism (correlating with the introduction of plastics in our society), have any studies been done analyzing their urine for the harmful chemicals?

Caroline (Cal) Baier-Anderson: I have not seen any studies looking at a relationship between plastics and autism. There have been a number of studies looking at different chemicals (from mercury to pesticides).

Remember that the "chemical revolution" that resulted in the widespread use of plastics also resulted in the use of pesticides and numerous other synthetic chemicals.


Washington, DC: I understand from the extensive media coverage how the BPA may leach from plastic containers into food and thereby pose a risk, but I wondered how CDs can cause problems. (I noted in the Post article that it said BPA is found in CDs.) Does that mean we should not let children handle them?

Caroline (Cal) Baier-Anderson: While I would not expect CD's to leach BPA through contact (although to my knowledge no one has studied this), for non-food/beverage uses, I would be more concerned about worker exposures, or direct releases to the environment during manufacture (global production tops 6 billion pounds!). These "lifecycle" costs are important to consider, too!


storage v. heating: Thank you for this helpful discussion today. At this point I use plastics to store food and heat it only in ceramic, covered with glass, having understood leaching mostly to occur during heating. Is this accurate, or is it better to never use the plastics in the first place?

Caroline (Cal) Baier-Anderson: This is tricky - certain foods may create environments more conducive to leaching - such as the acidity in tomatoes. I have noticed storing some acidic foods in plastic containers seems to etch the plastic, which makes me nervous!

For acidic foods, perhaps you might want to use ceramic for storage, too.


Salinas, Calif.: Hi Caroline. Are there any standards for the inner linings (ceramic or otherwise) of steel/aluminum fluid containers that serve as alternatives to plastic water bottles?

Caroline (Cal) Baier-Anderson: Good question - I don't know for sure, but I assume that this in in FDA's jurisdiction as we are talking about products that come into contact with beverages.


Bethesda, Md.: We keep reading about not using harsh detergents in the dishwasher. Can you explain what "harsh detergents" are and recommend the best products to use in the dishwasher (i.e. powder vs. liquid, etc.). Additionally, we are learning not to put baby bottles in the dishwasher or sterilizer. Any thoughts on this...for a mom of a toddler (with many sippy cups!) and a baby coming at any moment; I just can't imagine boiling water in a saucepan to individually wash each bottle or sippy... and would I even need to do this if we use BPA free bottles? Many thanks for clarification and explanations.

Caroline (Cal) Baier-Anderson: You know, warm soap and water does remove harmful bacteria. I am not sure about newborns (I breastfed my babies) but for kids we don't need to sterilize the sippy cups. A soak in warm soapy water should do the job. Even with sterilization there is enough bacteria floating around the air and in house dust to cover whatever we disinfect (99.99% of the bacteria poses no health risk so when we disinfect we wipe out benign, or even good bacteria!)


Savannah, Ga.: In regards to Nalgene: I use them all over the place! I bought them primarily for camping, because they are tough and will tolerate boiling water (uh oh!), but I use them all the time because I have them, and I didn't want to keep using disposable alternatives. Is there a BPA-free material with all of the positive qualities of Nalgene? For me it's all about quality, not stature or bottle size.

Caroline (Cal) Baier-Anderson: Yes - it is definitely a problem. Many of the camping stores have alternatives on the shelves - aluminum body lined with ceramic, or other non-BPA material.

Check with the outfitters, or the manufacturers. I would expect more materials to be available soon, but we will have to hope that the producers of these materials have "learned their lessons" and tested these materials thoroughly, publishing the results so that they are available for scrutiny...


Washington, DC: How different are these studies from the false saccharine scare of the 1970s? The one where rats were force-fed saccharine until they got cancer in their fore-stomachs, an organ humans don't have.

Caroline (Cal) Baier-Anderson: Actually, this is the exact opposite!

Most of the industry-sponsored studies relied on high dosing of animals. The newer studies focus on low dose exposures that are similar to human exposures. These are the studies that document the biological effects that have resulted in all of this attention.


Arlington, Va.: My mother always reuses plastic water bottles and has been doing so almost every day for several years. Should I try to get her to stop?

Caroline (Cal) Baier-Anderson: Perhaps you might want to buy her a reusable non-BPA water bottle for Mother's Day!


Long Beach, Ca.: Can we make this simple? Are you saying I should stop using plastic around food? Are there ANY safe plastics for use in food? If so, what is the number they are stamped with? Thanks

Caroline (Cal) Baier-Anderson: The plastics that are considered to be the best choices have the following numbers: 1, 2, 4 and 5.

I wish I could deliver a really simple message, but I cannot, because there is not enough scientific data to provide a basis for recommendations.

What I am saying is that in the face of this uncertainty, as consumers there are choices we can make to reduce our reliance on materials containing chemicals of concern.

But we need the government, and indsutry to step up to the plate and provide us with more information regarding what chemicals are being used, what safety data we have, and what additional testing we need.


Los Angeles: I recall the line "plastics" from The Graduate. So, plastics wasn't the future after all. Are the dangers found in plastics also found in all those plastics I and many others grew up using in the 1960s and afterwards?

Caroline (Cal) Baier-Anderson: Since plastics are ubiquitous, it is hard to argue that plastics are not our future - but that doesn't mean that they are completely safe!

As I noted earlier - some plastics are considered to be safer than others. And we are learning more as we go along.

Essentially my argument is that we should not be doing this "as we go along" but before we use these materials!


Alexandria, Va.: I notice that you advocate replacing polycarbonate containers with other containers that do not leach BPA. What should we do with our polycarbonate containers? I assume that many will just throw them in the trash -- which could be a problem in Northern Virginia where incinerators could release BPA into the environment as a combustion byproduct.

Caroline (Cal) Baier-Anderson: Yes, this is a real problem. Right now, there are no alternatives to throwing them away, at least not that I know of.

I am sorry that I don't have any additional ideas on this.


animal epidemiology?: Are there epidemiological studies of animals giving us data on this issue? I was listening to an item on NPR about increased chemicals used to line cat food tins etc. might be leading to increased incidence of ... I think it was kidney failure. It seems to me there's a wealth of epidemiological information out there from vets that could inform our own human health. Are we using this?

Caroline (Cal) Baier-Anderson: This is a really interesting area of research. Environmental Working Group just published a study on chemicals found in household pets. The problem is that not all animals get equal care; some rarely see a vet, some are "put down" as soon as they fall ill so we don't get to identify the disease, etc. In theory it may provide a lot of useful information, but the scientists need to work a little harder to design a reliable study.


Baltimore: In an effort to replace my plastic lids, I recently purchased a silicone lid that is advertised to fit all containers. I realize it's not plastic, so would you consider this a safe alternative for the microwave?

Caroline (Cal) Baier-Anderson: Food grade silicone (or better - medical grade silicone) is considered to be a safer alternative.


Evanston, Ill.: We have tried to eliminate most plastics but our daughter is very attached to her pacifiers. I noticed companies make latex or silicone versions -- is one better than the other?

Caroline (Cal) Baier-Anderson: Silicone and latex are generally considered to be safer alternatives. SOme studies have suggested that some chemicals may leach from latex, and some people are allergic to latex.


Caroline (Cal) Baier-Anderson: This has been really interesting and challenging for me. Thank you for all of the great questions, and thanks to the Washington Post for giving me this opportunity.


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