Female Breasts Are Bigger Than Ever, But Under Threat Men and chemicals equally assault the vulnerable female breast.

May 7, 2012 -- Florence Williams gets right to the bosom of her new book in its first line, reeling off names for the most beloved part of the female anatomy: "Funbags. Boobsters. Chumawumbas. Dingle bobbers. Dairy pillows. Jellybonkers. Nim nums."

So begins William's humorous, but deadly serious treatise, "Breasts: A Natural and Unnatural History."

"We love breasts, yet we can't quite take them seriously," she writes. "We name them affectionately, but with a hint of insult. Breasts embarrass us. They're unpredictable. They're goofy. They can turn both babies and grown men into lunkheads."

Breasts feed us, nurture us and excite us. But the most versatile organ in the female body can also kill us. They are made up of fat and estrogen receptors -- so they "soak up pollution like a pair of soft sponges," she writes.

One in eight women will have breast cancer in her lifetime.

Williams, an award-winning science writer, investigates why breasts are assaulted equally by men and a rising number of chemicals in the environment.

She follows breasts through their natural life cycle from puberty to changes during pregnancy, breastfeeding and menopause. And she wonders about their psycho-sexual meaning, writing, "big breasts get a lot of attention."

Breasts are, indeed, bigger than ever, according to her research. The average-sized breast for an American woman is now a C cup and lingerie stores sell sizes from H to KK.

Or, more precisely, the average breast weighs just over a pound, but can double in pregnancy. The largest (enhanced) breast in the world is 21 pounds or a 38KKK, the equivalent of 1.3 gallons of liquid.

Williams, 45, was inspired to write the book when she agreed to participate in a study of her breast milk when she was nursing her daughter. The results were startling -- her milk was full of chemicals, from pesticides to flame retardants

"There were reports about toxic and chemical contaminants showing up in breast milk -- it was a great way to tell the story first-person," she told ABCNews.com. "I realized there was so much about breasts people don't know."

Today Williams' daughter is 8, and she worries about research that shows girls are beginning puberty and developing breasts younger, perhaps because of exposure to pollutants.

"There are hundreds of chemicals coursing through our blood," she said.

She also explores evolutionary questions. Why do men like big boobs? They are a "sexual signal" that reveals a young woman is mature enough to reproduce. Breasts tend to droop when women age.

But other researchers suggest that the human breast -- large and round with a dangling nipple -- is unique in the animal world, perhaps to allow the mother to hold the infant in her arms, nurturing the child longer.

"Natural selection versus sexual selection turns out to be a lot more contentious than I expected," said Williams.

Mother's milk is "always the right temperature; it has the correct balance of lipids, proteins and sugars. It is medicinal, nutritious, and, to a baby, delicious," according to Williams.

Her detailed study includes oddities never considered: Breast milk contains substances similar to marijuana and is sold on the Internet for 262 times the price of oil, she wrote.

Another interesting factoid: Hour-glass figure Barbie was created by Ruth Handler, a cancer-survivor responsible for inventing the first breast prosthesis in the 1970s.

Women, too, have been obsessed by breast size.

Before silicone, women stuffed their bras with Kleenex and socks, until the earliest implants were introduced in the early 20th century, including glass balls, ivory, wood chips, peanut oil and ox cartilage. Eventually paraffin was used -- until it melted in the sun and created lumps.

On the 50th anniversary of silicone implants, Williams interviewed Timmie Jean Lindsey, who was the first recipient in 1962.

Now, at 79, she has health problems, including rheumatoid arthritis, an autoimmune disease.

"She told me she was more or less satisfied with her implants, despite the fact that they turned hard, ruptured and she had shooting pains in her chest," said Williams.

In 1976, the FDA began regulating silicone after reports of infections, gangrene and several deaths.

Breast Implants Are Most Popular Cosmetic Surgery

According to Williams' research, an estimated 289,000 women had enlarged their breasts in 2009, the most popular cosmetic surgery. In all, more than 5 million women in the US have implants.

She describes her visit to see a Texas plastic surgeon who performs 800 enlargements a year. She described the clinic as, "Trump Plazas meets Jiffy Lube."

"The plastic surgery industry is masterful at the hard sell," said Williams. "They have convinced women that it's just a simple cosmetic product, like buying a bottle of moisturizer."

Though tempted to try the implants out, she realized, "a lot of perfectly nice breasts ended up looking like water balloons on a skinny rib cage."

In Western culture, breasts are "sexualized to the point where have trouble taking them seriously," she said. "Young girls, rather than being in awe of evolutionary miracles, are ashamed of their breasts because they don't look like pornography."

But her biggest concern is the vulnerability of breasts -- cancer rates have doubled since the 1940s, according to Williams.

Although Williams can't say with certainty that chemicals in the environment cause breast cancer, she notes that the breast is the one organ in the body that is not fully developed until adulthood -- and even the last trimester of pregnancy.

"For many years, the breast cells are undifferentiated and more vulnerable and so are susceptible," she said.

Girls who go through puberty earlier are also at greater risk for breast cancer as adults. "We don't know why," she said.

She notes that in Europe chemicals must be proved safe before entering the marketplace. "We have the opposite and don't take them off the market until they are proven harmful," she said.

Advances in science give reason for optimism, according to Williams. But "government regulatory agencies and the public in general are generally blind to where science is."

"Our bodies are intimately connected to the world around us," said Williams. "If we live in an environment filled with pollution, these things will and do affect our health."