Dr Dingle's Blog / birth defects

Mothers BPA levels linked with birth defects.

Mothers BPA levels linked with birth defects.

Evidence from animal studies shows that prenatal exposure to bisphenol A (BPA), a ubiquitous endocrine-disrupting chemical, is associated with adverse reproductive outcomes in females and males. In females exposure during early gestation, a critical period for reproductive development, is of particular concern. The Anogenital distance (AGD) is a sensitive biomarker of the fetal hormonal balance and a measure of reproductive toxicity in animal studies. In some studies, the daughters of BPA-exposed dams have shorter AGD than controls.

The results of this study showed BPA was detectable in 94% of women. In analysis of the 381 eligible subjects, maternal BPA concentration was inversely associated with infant AGD-AC

In support of animal studies this human study shows that BPA may have toxic effects on the female reproductive system in humans, as it does in animal models. Higher first-trimester BPA exposure was associated with significantly shorter AGD in daughters, suggesting that BPA may alter the hormonal environment of the female fetus.

Bisphenol A (BPA) is a synthetic chemical widely used in consumer products, including food and drink containers, thermal receipts, medical equipment, and other plastic products. BPA is detectable in over 90% of the population in the United States, and may act on the endocrine system in numerous ways, including binding to and activating numerous nuclear and membrane endocrine receptors, and stimulating changes in estrogen, androgen, progesterone, and thyroid hormone activity.

Dozens of studies in humans have examined BPA exposure in relation to a wide range of health end points, including reproductive, perinatal, and pediatric outcomes. Many animal studies and in vitro studies show that many tissues and organ systems (including the mammary gland, prostate gland, adipose tissue, reproductive system, and brain) are sensitive to BPA. In animal and human studies, BPA can cross the placenta to enter fetal circulation. Because fetal development is a period of rapid cell proliferation and differentiation, tissue development, and organ growth, prenatal exposure to environmental chemicals such as BPA may be of particular concern.

source

https://ehp.niehs.nih.gov/ehp875/

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Common household disinfectants linked with birth defects, miscarriages and fertility.

Common household disinfectants linked with birth defects, miscarriages and fertility.

Quaternary ammonium compounds (QACs) are antimicrobial disinfectants commonly used in commercial and household settings and everyone is virtually exposed to these chemicals every day. Two common quaternary ammonium compounds, alkyldimethylbenzyl ammonium chloride (ADBAC) and didecyldimethyl ammonium chloride (DDAC), are combined in common cleaners and disinfectants.

In this study introduction of a cleaner containing ADBAC+DDAC in the living chambers caused neural tube defects (NTDs) in mice and rats. They found increased neural tube defects with exposure to the disinfectant combination in both rats and mice. The neural tube defects persisted for two generations after cessation of exposure.

They also found that male exposure alone was sufficient to cause neural tube defects. Equally significant, ambient exposure from disinfectant use in the cage they were kept in, influenced the levels of neural tube defects to a greater extent than oral dosing. So the ambient exposure through the air and surfaces had more impact than the feeding.

These results clearly demonstrate that ADBAC+DDAC in combination are teratogenic (birth defects) to rodents. Given the increased use of these disinfectants, further evaluation of their safety in humans and their contribution to health and disease is essential.

Quaternary ammonium compounds (QACs) are a large class of chemicals used for their antimicrobial and antistatic properties. They are common ingredients in cleaners and disinfectants, hand wipes, food preservatives, swimming pool treatments, laundry products, shampoos, conditioners, eye drops, and other personal care products. QACs have been in use for over 60 years, but the number of products containing QACs has increased recently as the versatility of these compounds is recognized. Over time, the chemical structure has been altered to increase antimicrobial and surfactant efficacy resulting in multiple generations of these products. Many products now contain a combination of two or more QACs. Extensive use of QACs results in ubiquitous human exposure, yet reproductive toxicity has not been evaluated.

Because chemical mixtures can act synergistically to produce greater toxic effects than the sum of the individual components, evaluation of common mixtures is essential in the evaluation of chemical risk.

This study was initiated because some laboratories which breed and test with mice and rats had noticed some anomalies. One laboratory noted abrupt declines in mouse colony productivity, along with declines in fetal health, that coincided with the introduction of disinfectants containing the QACs, alkyl dimethyl benzyl ammonium chloride (ADBAC) and didecyl dimethyl ammonium chloride (DDAC). Several years later, the laboratory encountered breeding problems and neural tube birth defects (NTDs) that began shortly after a change in room disinfectants. These experiences pointed to the QAC disinfectant but could not confirm toxicity because neither incident tested QACs under experimental conditions.

In an earlier study by the same team reproductive studies demonstrated that QACs adversely affect both male and female fertility and fecundity in rodents (Melin et al., 2014, 2016). Decreased reproductive performance in laboratory mice coincided with the introduction of a disinfectant containing both alkyl dimethyl benzyl ammonium chloride (ADBAC) and didecyl dimethyl ammonium chloride (DDAC). QACs were detected in caging material over a period of several months following cessation of disinfectant use. Breeding pairs exposed for six months to a QAC disinfectant exhibited decreases in fertility and fecundity: increased time to first litter, longer pregnancy intervals, fewer pups per litter and fewer pregnancies. Significant morbidity in near term dams was also observed. In summary, exposure to a common QAC disinfectant mixture significantly impaired reproductive health in mice.

 

Source 1

Ambient and dosed exposure to quaternary ammonium disinfectants causes neural tube defects in rodents. Hrubec TC et al 15 June 2017. http://onlinelibrary.wiley.com/doi/10.1002/bdr2.1064/full

Source 2

Exposure to common quaternary ammonium disinfectants decreases fertility in mice.

Melin VE1, Potineni H1, Hunt P2, Griswold J2, Siems B3, Werre SR4, Hrubec TC5.Reprod Toxicol. 2014 Dec;50:163-70. doi: 10.1016/j.reprotox.2014.07.071. Epub 2014 Aug 14.

 

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Common household disinfectants linked with birth defects, miscarriages and fertility.

Common household disinfectants linked with birth defects, miscarriages and fertility.

Quaternary ammonium compounds (QACs) are antimicrobial disinfectants commonly used in commercial and household settings and everyone is virtually exposed to these chemicals every day. Two common quaternary ammonium compounds, alkyldimethylbenzyl ammonium chloride (ADBAC) and didecyldimethyl ammonium chloride (DDAC), are combined in common cleaners and disinfectants.

In this study introduction of a cleaner containing ADBAC+DDAC in the living chambers caused neural tube defects (NTDs) in mice and rats. They found increased neural tube defects with exposure to the disinfectant combination in both rats and mice. The neural tube defects persisted for two generations after cessation of exposure.

They also found that male exposure alone was sufficient to cause neural tube defects. Equally significant, ambient exposure from disinfectant use in the cage they were kept in, influenced the levels of neural tube defects to a greater extent than oral dosing. So the ambient exposure through the air and surfaces had more impact than the feeding.

These results clearly demonstrate that ADBAC+DDAC in combination are teratogenic (birth defects) to rodents. Given the increased use of these disinfectants, further evaluation of their safety in humans and their contribution to health and disease is essential.

Quaternary ammonium compounds (QACs) are a large class of chemicals used for their antimicrobial and antistatic properties. They are common ingredients in cleaners and disinfectants, hand wipes, food preservatives, swimming pool treatments, laundry products, shampoos, conditioners, eye drops, and other personal care products. QACs have been in use for over 60 years, but the number of products containing QACs has increased recently as the versatility of these compounds is recognized. Over time, the chemical structure has been altered to increase antimicrobial and surfactant efficacy resulting in multiple generations of these products. Many products now contain a combination of two or more QACs. Extensive use of QACs results in ubiquitous human exposure, yet reproductive toxicity has not been evaluated.

Because chemical mixtures can act synergistically to produce greater toxic effects than the sum of the individual components, evaluation of common mixtures is essential in the evaluation of chemical risk.

This study was initiated because some laboratories which breed and test with mice and rats had noticed some anomalies. One laboratory noted abrupt declines in mouse colony productivity, along with declines in fetal health, that coincided with the introduction of disinfectants containing the QACs, alkyl dimethyl benzyl ammonium chloride (ADBAC) and didecyl dimethyl ammonium chloride (DDAC). Several years later, the laboratory encountered breeding problems and neural tube birth defects (NTDs) that began shortly after a change in room disinfectants. These experiences pointed to the QAC disinfectant but could not confirm toxicity because neither incident tested QACs under experimental conditions.

In an earlier study by the same team reproductive studies demonstrated that QACs adversely affect both male and female fertility and fecundity in rodents (Melin et al., 2014, 2016). Decreased reproductive performance in laboratory mice coincided with the introduction of a disinfectant containing both alkyl dimethyl benzyl ammonium chloride (ADBAC) and didecyl dimethyl ammonium chloride (DDAC). QACs were detected in caging material over a period of several months following cessation of disinfectant use. Breeding pairs exposed for six months to a QAC disinfectant exhibited decreases in fertility and fecundity: increased time to first litter, longer pregnancy intervals, fewer pups per litter and fewer pregnancies. Significant morbidity in near term dams was also observed. In summary, exposure to a common QAC disinfectant mixture significantly impaired reproductive health in mice.

 

Source 1

Ambient and dosed exposure to quaternary ammonium disinfectants causes neural tube defects in rodents. Hrubec TC et al 15 June 2017. http://onlinelibrary.wiley.com/doi/10.1002/bdr2.1064/full

Source 2

Exposure to common quaternary ammonium disinfectants decreases fertility in mice.

Melin VE1, Potineni H1, Hunt P2, Griswold J2, Siems B3, Werre SR4, Hrubec TC5.Reprod Toxicol. 2014 Dec;50:163-70. doi: 10.1016/j.reprotox.2014.07.071. Epub 2014 Aug 14.

 

Read more →