Answer to subscriber's question
by aajonus vonderplanitz, ph.d. nutrition
Hi Aajonus. Did you know that BPA is on the interior of Ball and Kerr Canning jar lids? I was finally able to talk with a person from the Ball Company about their rubber rimmed lids with the white-coated interior and their plastic storage caps. The person (Jessica) looked in her data sheets and confirmed that the white interior lid contains BPA. She said it is a small amount. She said it would take a 150 pound person 2,400-4,300 lids with the BPA in them to reach the maximum safe daily limit required by the FDA. She went on to say that the BPA must be in the lids according to FDA rules to prevent corrosion. The lid with the white interior is made from a modified vinyl and is not enamel. She also said the modified vinyl does not have PVC in it but definitely has the BPA.
The Ball plastic storage caps are made from polypropylene which is a #5 plastic (1). There is no BPA or PVC in the plastic storage caps. She further stated that the Ball Company is researching a new lid which would be BPA free. All my best.
Aajonus: Hi, Christina. The manufacturer and distributor of Ball and Kerr lids are supposedly the same company now. I was told by a representative of the company who licensed the manufacturing and sales of those lids that the Ball company does not manufacture or sell lids anymore. The representative claimed that both lids were sealed with plastic coatings.
However, when I scraped the goldish underside of Kerr lids, a clear-undercoat easily curled like plastic. Therefore, I do not use Kerr lids. When I scraped the white-undercoat of Ball lids, there was no curled material. When I pressed and cut hard into the white-undercoat of Ball lids, the coating chipped but did not curl or fragment. So, if the Ball white-undercoat is plastic, it is a variety that does not dissolve with food.
The only way BPA (2) would leach into food is if the undercoat were soft enough to dissolve in food. That may be true of the Kerr brand but not the Ball. The main foods I use that touch the lids are vegetable juices and milk. Neither are caustic and could not dissolve the undercoat and release BPA from the Ball brand. However, I mix my fruits and creams together in jars. Some of the acidic fruits such as pineapple could dissolve the coating but when I tested for that, I could not find any etching of the coating under a microscope unless the pineapple (without cream) directly touched the Ball lid's undercoat for several weeks.
The coating of at least 2,300 lids would have to completely dissolve into food to cause a severe reaction from BPA. I estimate that that would take about 500 years. The trace amount of BPA that might be released over many months from one lid would not be enough to store and harm the bodies of people eating my Primal Diet(tm). However, I have one caution: Once the white-coating has chipped it should not be used; recycle it with cans.
(1)Plastics are made of various toxic compounds and are graded as # 1-7. #5s are polypropylene (PP). Its characteristics include strength, toughness, barriers to moisture and resistance to heat, chemicals, grease and oil. #5 grade plastics are used for microwaveable ware, kitchenware, yogurt contains, margerine tubs, microwaveable disposable take-away containers, disposable cups and plates.