Athe mercenians now survive puberty considerably earlier than in decades earlier, a trend that is associated with physiological and psychological risks. The various factors considered as early puberty include obesity, toxic stress and environmental factors. A historical study published Monday looks at a particular type of environmental element – chemicals in household items.
Long-term study on mothers and children published in Human reproduction found that the occurrence of female puberty was associated with exposure to chemicals such as phthalates, parabens and antibacterial agent triclosan. These products are used in personal care products, such as some brands of perfumes, cosmetics and toothpaste. The same result was not found in boys' populations, whose puberty time was also examined in this study.
"We know over the past 15 to 20 years that girls enter puberty at an earlier age than they used before," said Ph.D., University of California, Berkeley associate professor Kim Harley. tells Conversely. "We certainly know that obesity plays a role in that, but now, too, we know that chemicals that disturb the hormone that are found in our homes and in our environment could be an additional factor contributing to it."
While it is premature to say whether these widely used chemicals are definitely causing early puberty, Harley believes that "we need to pay attention to these chemicals and we begin to have enough information about them to be concerned."
The discovery of the cause of early puberty is important for scientists because the phenomenon is associated with a greater risk of developing depression, a greater risk of pregnancy in teenage years, and an increased likelihood of developing diseases such as breast cancer and heart disease.
The findings of the new study are based on data on pregnant women and the children who gave birth, who were enrolled in the Salinas Health Care Assessment Center for Mothers and Children from 1999 to 2000. When women were about 14 and 27 weeks' gestation gave scientists an agreement to examine their urine samples for concentrations of phthalates, parabens and phenols. After women gave birth, the team collected samples of urine and estimated the puberty in the development of 179 girls and 159 boys. Every nine months between the ages of 9 and 13, scientists have applied to see how puberty affects children.
In general, 90 per cent of urine samples showed a concentration of all the compounds for which they were tested. It was found only in 73 per cent of pregnant mothers and 69 per cent of samples taken from nine-year-olds.
Mothers whose samples contain diethyl phthalate and triclosan had daughters who had previously entered puberty. For every doubling of triclosan in the mother's urine, the timing of the first menstrual cycle of girls was shifted in just one month and for each doubling in phthalate indicator samples, the development of girls' embarrassing hair shifted 1.3 months earlier. Urine samples taken from 9-year-old girls again sealed that, for each doubling of paragon concentrations, the time of breast development and public hair, as well as their first period, a mother happened earlier on average.
One reason why these chemicals can affect puberty is because they are all known endocrine disorders. Previous studies of animals and humans have shown that endocrine disorders have the capacity to mimic, block or otherwise affect the hormones of the body.
"They can bind to hormonal receptors such as estrogen receptors and affect changes in our body," explains Harley. "We are concerned about this. We know from animal studies that these chemicals can influence the development of rats, especially if exposure occurs in the uterus, and now we are beginning to explore from human studies that can influence development."
What is difficult to share the results of this study, says Harley, is that for now everyone can say that these are "chemicals that are worried." The Centers for Disease Control and Prevention readily recognize that there is widespread exposure phthalates and parabens, with the majority of Americans tested with evidence of these chemicals in their urine. However, the agency says finding measurable volumes of these chemicals "does not mean that they cause harmful health effects".
Harley hopes that regulators review studies as her when they continue to implement policy decisions and regulations. From now on, there is no established reference level that states when it is no longer safe to be exposed to these chemicals. It is not illegal to have them in personal care products because science is not strong enough to say that they absolutely cause harmful health effects. They are controversial chemicals, and about 70 percent of Americans have them in their bodies.
"These chemicals are basically everywhere," says Harley. "The regulation is not really there and science is still unchangeable, but for people who are worried, there are things you can do."
Tip is simple: Reducing exposure to chemicals with concerns about changing personal care products you use and buying products that do not contain them. Scientists can not say with certainty what will change for you, if you do it, but that certainly can not hurt.