For many baby boomers, their childhood memories may include running behind DDT trucks, riding in the car while mom and dad smoked cigarettes or playing with the mercury out of a broken glass thermometer. While it may have seemed like harmless fun at the time, many boomers may now wonder whether these activities could have had any serious health repercussions.

“We’ve all had exposures to a lot of potentially hazardous chemicals,” Dr. William J. Hall, a professor of medicine at the University of Rochester and director of the Highland Hospital Center for Healthy Aging, told FoxNews.com. “Particularly for someone who grew up in the 1940s, ’50s, and ’60s, they probably have had as much as any group of humans because of industrial growth after World War II. There were no restrictions around.”

Hazards like secondhand smoke, DDT, mercury and lead exposure may be linked to an increased risk for a range of health issues, including cancers and neurological disorders, but experts say there’s a lack of data available to study health outcomes of these widespread exposures for adults born between 1946 to 1964.

“They’re the first generation that comes around in what we call the post-epidemiological revolution years,” Christian Warren, an associate professor of history at Brooklyn College and historian of modern American public health told FoxNews.com. “Prior to the ’60s, most medical and public health attention focused on infectious and acute problems; environmental and toxicological issues generally took a back seat.”

Warren cited the 1964 Surgeon General’s Report on Smoking and Health, the first government report highlighting the negative health consequences of tobacco use , as a landmark study – one of the first to analyze the effects of disease at a population level.

However, the correlation between environmental exposure and disease isn’t always so clear cut.

“There’s a misnomer that disease is attributed to either genetic factors or environmental factors. It’s important to understand that disease is attributable to both,” Eric Boerwinkle, director of the Division of epidemiology, human genetics and environmental sciences at The University of Texas School of Public Health told FoxNews.com. “We’ve all been exposed, whether to secondhand smoke or diesel fuel particulates, [these are] risks involved in living our everyday life and both the individuals and society try to minimize these risks.”

Secondhand smoke: “It’s unbelievable how common smoking was back then.”
In the 1950s, 50 percent of men and 30 percent of women smoked, according to the Centers for Disease Control and Prevention (CDC). After the 1964 Surgeon General report, smoking rates for men began to fall almost immediately.

“The baby boom really brackets the high rates of smoking in the U.S.,” Diane Lauderdale, professor of epidemiology and chair of the department of health studies at the University of Chicago told FoxNews.com. “The majority of children were probably exposed… it was thought that having a mother who smoked put you at a higher risk of exposure.”

Risks related to secondhand smoke exposure occur mostly in childhood and can include increased rates of sudden infant death syndrome [SIDS] and respiratory tract and ear infections, Lauderdale said. Asthma may also be a long term side effect.

Dr. Frederica Perera, director of the Columbia Center for Children’s Environmental Health and professor of Environmental Health Sciences at Columbia’s Mailman School of Public Health, has been following a group of mothers and their children since 1998, when the women were pregnant. They’ve found an association between secondhand smoke exposure in utero and early life and problems with neurological development, including cognitive or behavioral problems.

Recent research from the Cincinnati Children’s Hospital Medical Center linked exposure to environmental tobacco smoke, even at low levels, with decreases in cognitive skills and behavioral problems in children and adolescents. Researchers also found prenatal exposure to tobacco smoke may lead to a 2.4 fold increased odds of ADHD.

However, the link between childhood exposure to secondhand smoke and a person’s life-long risk of developing cancer is more controversial.

“Secondhand exposure in life is definitely a risk, but if you only [had exposure] in childhood and then were in a smoke-free environment, it’s unclear whether there is a risk; findings are mixed,” Lauderdale said. “It’s unbelievable to think how common smoking was back then,” she said.

DDT: “Kids would just follow the truck.”
Dichlorodiphenyltrichloroethane (DDT) was widely used as an insecticide during baby boomers’ childhood years. It was banned in 1972 because of its harmful environmental effects and the potential health risks it posed to humans – but these long-lasting toxins accumulated and have persisted in the environment

Most of the boomer-aged experts FoxNews.com spoke with had vivid memories of what – at the time – was considered harmless, even fun, exposure to DDT.

“I remember in the early ’60s, at the drive-in movie between the two features… they’d just spray it between the lanes,” Lauderdale said. “In college I went to a summer camp in Maine and they’d spray it every couple of weeks and kids would just follow the truck.”

However, experts still don’t fully understand all the effects of the chemical on human health.

“Evidence is only moderate that DDT mildly elevates risk of cancer for the liver, pancreas and maybe breast,” Lauderdale said. “Evidence is mixed because people can’t report their exposure. It was a widespread exposure during those years with unclear consequences.”

Mercury: “The real danger wasn’t if you played with it.”
While mercury thermometers have since been phased out of home use, they were common when baby boomers were children. When broken, the glass-like bubbles of mercury contained in a thermometer could be a tempting plaything for children. However, experts say boomers concerned about exposure to the element shouldn’t worry too much.

According to the Environmental Protection Agency (EPA), elemental (metallic) mercury, when inhaled through the lungs as a vapor, can cause side effects such as emotional changes (e.g., mood swings, nervousness), insomnia and headaches. Higher exposures may lead to kidney damage, respiratory failure and death. Acute poisoning may result in fever, fatigue, and signs of pneumonitis.

“It’s only a danger if it’s vaporized,” Lauderdale said. “The real danger wasn’t if you played with it, but if it fell on the rug, got vacuumed and vaporized. If they didn’t a have acute mercury poisoning, I don’t think anyone has the consequences of the long-term effect.”

In other words, exposure to high levels of mercury would have immediate health effects – but doesn’t seem to pose a threat years later.

Yet, exposure to high levels of mercury in fish is a more relevant concern. In 1956, a chemical company dumped mercury into the Minamata Bay near Minamata City, Japan, contaminating fish and exposing any resident who consumed fish to high levels of mercury. Researchers later revealed that children born to women who ate the tainted fish had high incidences of cerebral palsy, despite the fact that many of their mothers themselves were not affected.

“We know from our work and the work of many others that this period of development in utero and in early childhood is especially sensitive to toxicants,” Perera said.

“You should think about, ‘What can I do?’ not ‘Woe is me.’”
Overall, some experts say baby boomers should focus more on improving their current quality of life rather than worry about the impact of environmental exposures they may have had during childhood.

“Biologically, we turn over all of our cells frequently. I’m very suspicious and critical when people become negative about taking charge of their own health because of something that happened in their past. They should think about ‘What can I do?’ not ‘Woe is me,’” Hall said.

Compared to 20 to 25 years ago, medicine is better at stabilizing chronic conditions and screening older adults.

“Because people are living longer and generally doing better, our younger older adults tend to be fitter, and healthier,” Dr. Nisha Rughwani, assistant professor of geriatrics at the Icahn School of Medicine at Mount Sinai, told FoxNews.com..

And while many seniors may be looking forward to retirement, truly enjoying it will require more than just stepping away from work.

“People who are “successful” at retirement age, who say ”I’m having the best years of my life,” invariably are the people who are doing something about their health,” Hall said.