Students from El Colegio Charter School in Minneapolis stand before a classroom of mothers and toddlers at an Early Childhood and Family Education, or ECFE, class. The kids are there to teach them about BPA.
This chemical is commonly found in many plastic products, like water bottles, baby bottles, and sippy cups. BPA is used to make these products hard, shatter resistant, and often clear in color. It's also used to coat aluminum and tin food cans.
But studies have shown that this chemical leaches when it is exposed to heat or scratched at the surface -- for example, when a water bottle is washed with a harsh detergent and sponge.
Keith Weller, 16, takes quick glances at his index cards. He tells the class that BPA is more than an industrial chemical used in plastics. It's also a synthetic estrogen.
"Even at low exposure levels, bisphenol A or BPA is a potent hormone disruptor," says Weller. "As low as two parts per billion BPA exposure affects our health. That's pretty much two grains of salt for 110 pounds of mashed potatoes."
In animal studies, BPA is linked to causing breast and prostate cancers, low sperm count and miscarriages. Research shows possible links to early puberty and obesity.
Those most vulnerable to the chemicals are the unborn and small children, because hormonal imbalances can greatly affect them during their developmental stages.
Geochemist Bill Toscano with the University of Minnesota believes the students' work is important. He says BPA is everywhere, and while everyone should minimize their exposure, pregnant women and mothers should take extra caution to limit their exposure.
"When a women is pregnant, all things are going on with the baby, and it's a sea of estrogen anyhow in the womb," says Toscano. "But what these things are doing, we don't know. From the animal studies, it could be that these are causing the same effects in humans."
Toscano suggests mothers should avoid hard plastics, and even soft dark plastics used for some nipples on baby bottles and pacifiers, because they contain another synthetic estrogen called phthalates.
Students from El Colegio Charter School learned about BPA in their environmental class that uses a program by the nonprofit Eco Education. The class allows them to research and identify local environmental issues. Once they vote on the issue they're most interested in, they carry out a hands-on community improvement project.
BPA is commonly found in many plastic products, like water bottles, baby bottles, and sippy cups. BPA is used to make these products hard and shatter resistant.
Faith Krogstad is with Eco Education. She says several guest speakers visited the class. One doctor in particular talked about something called "the body burden."
"We produce a lot of toxic chemicals. We don't know a lot of information about them," says Krogstad. "These chemicals get into breast milk and cross through the placenta, and newborns end up with a lot of toxic chemicals in the blood before they're exposed to the environment."
The doctor told them one way mothers actually get rid of a lot of chemicals built up in the body is by giving birth.
"So the baby ends up with a toxic debt that they carry into the world when they're born," says Krogstad.
For 10th grader Mary Hampton, learning about BPA and body burden was timely.
"There's a girls group at our school and we needed to raise money, so we were thinking about selling Nalgene bottles," says Hampton. "And then we were learning about this chemical and I'm like, wait. So at the next meeting we had, I was like, 'Hold on, there's a chemical in the Nalgene bottles that could give us real serious health problems,' so we stopped."
Hampton says she spreads the word about BPA outside of her class project, among her family, friends, and at her church.
After being shocked about how widespread the chemical is, the students wanted to teach mothers about BPA and how to read labels for safe baby products. A grant by Eco Education funded their project.
The students presented their BPA findings to their entire school and this ECFE class, where even mothers who knew a little bit about BPA still had questions.
"Even in some sippy cups, they don't even list a number on the products, so are there ways for us to know about companies, to be looking for [the number]?" asks a mother in the classroom.
The students encouraged parents to call companies that don't label their products to get that information. Most manufacturers label their plastic products with a recycling symbol. The students told parents that safer plastics are labeled with recycling numbers 1, 2, 4, and 5. They were able to give out BPA-free baby products they purchased with their grant money.
In the upcoming legislative session, lawmakers are expected to consider a bill to eliminate BPA and phthlates from baby products for children 3 and under.