November 27, 2023
Although there are numerous kinds of perfluoroalkyl substances (PFAS), the primary ones used in the manufacture of fluoropolymers are perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). Because of their strong water-repelling properties, fluoropolymers are used in stain repellents, polishes, paints, and other coatings, as well as in water-resistant outdoor clothing. They are long-lasting and therefore both pervasive in the home and environment and subject to accumulation in our bodies, especially in urbanized and industrialized areas. These substances can be passed from mother to child both through the placenta and through breastfeeding.
With support from the European Union, a large international team of European and North American researchers set out to investigate possible associations between early-life exposure to PFOS and PFOA and subsequent ADHD. They performed a meta-analysis on nine European population studies encompassing 4,826 mother-child pairs.
Participants were restricted to live-born single births with data on concentrations of PFOS and/or PFOA, and available information on ADHD diagnosis or symptoms.
Because a) some studies looked at maternal serum/plasma, others at maternal breast milk; b) timing of sample collection varied (first trimester, delivery); and c) children's levels during the first two years of life were unavailable (ethical constraints limit drawing blood samples from infants), the team used a validated pharmacokinetic model of pregnancy and lactation to estimate pre-and postnatal concentrations of PFASs in offspring.
The team adjusted for seven potential confounders: maternal pre-pregnancy body mass index, maternal age at delivery, maternal education, maternal smoking, number of previous children, duration of breastfeeding, and child sex.
With these adjustments, no association was found between estimated exposures to either PFOS or PFOA at birth, at three months, and at two years and subsequent diagnosis or symptoms of ADHD. While the raw data showed slightly higher odds for girls than for boys to develop ADHD with identical exposures, the differences were statistically non-significant.
Joan Forns, Marc-Andre Verner, Nina Iszatt, Nikola Nowack, Cathrine Carlsen Bach, Martine Vrijheid, Olga Costa, Ainara Andiarena, Eva Sovcikova, Birgit Bjerre Høyer, Jürgen Wittsiepe, Maria-Jose Lopez-Espinosa, Jesus Ibarluzea, Irva Hertz-Picciotto, Gunnar Toft, Hein Stigum, Mònica Guxens, Zeyan Liew, and Merete Eggesbø https://doi.org/10.1289/EHP5444.
Organic farming aims to protect biodiversity, promote animal welfare, and avoid using pesticides and fertilizers made from petrochemicals. Some pesticides are designed to target insects’ nervous systems but can also affect brain development and health in larger animals, including humans.
Many people believe organic food is healthier than conventionally produced food, which might be true for certain foods and health factors. But does eating organic food during pregnancy impact the chances of a child developing ADHD or autism spectrum disorder (ASD)?
In Norway, researchers can use detailed national health records to study these connections on a population-wide level, thanks to the country’s single-payer healthcare system and national registries.
The Norwegian Mother, Father, and Child Cohort Study (MoBa) invites parents to participate voluntarily and has a 41% participation rate. The study includes:
For this research, a team tracked 40,707 mother-child pairs from children born between 2002 and 2009. They used questionnaires to measure how much organic food mothers consumed during pregnancy. ADHD and ASD symptoms in children were assessed using validated rating scales.
The final analysis included:
The researchers adjusted for factors like maternal age, education, previous pregnancies, BMI before pregnancy, smoking and alcohol use during pregnancy, birth year and season, and the child’s sex.
The researchers concluded that eating organic food during pregnancy has no meaningful effect on the likelihood of a child developing ADHD or ASD. They stated, “The results do not indicate any clinically significant protective or harmful effects of eating organic food during pregnancy on symptoms of ADHD and ASD in the offspring. Based on these findings, we do not recommend any specific advice regarding intake of organic food during pregnancy.”
Infertility affects about one in six couples worldwide. To address this, medical experts have developed Assisted Reproductive Technologies (ART), including In Vitro Fertilization (IVF) with or without Intra-Cytoplasmic Sperm Injection (ICSI).
Some research suggests that children conceived through ART might have higher rates of intellectual disabilities, cerebral palsy, cancer, and neurological issues compared to children conceived naturally. However, studies looking at a possible link between ART and ADHD have produced mixed and conflicting results.
Until now, there hasn’t been a meta-analysis examining the connection between ART and ADHD. A South Korean research team has conducted the first systematic review and meta-analysis on this topic. Their final analysis included eight studies with a total of over ten million participants, comprising six cohort studies and two cross-sectional studies.
The research focused on two types of studies:
Both types of studies are observational, meaning they don’t involve controlled experiments and can be influenced by confounding factors. So they can document interesting associations, not causality. The studie were mostly large-scale national studies and used clinical ADHD diagnoses.
The researchers concluded that while there may be a small association between ART and ADHD, the effect is minimal, and the results are influenced by differences in study designs. They advised interpreting these findings with caution, noting, “The limited effect size and inherent heterogeneity underscore the need for cautious interpretation.”
Periodontitis, commonly known as gum disease, is a condition where the gums become inflamed. If untreated, it can cause the gums to pull back from the teeth, exposing their base, which may eventually lead to loose teeth or tooth loss. While this condition mostly affects adults, it’s also common among teens who don’t floss or brush their teeth properly.
Until now, only a few small studies have looked at a possible link between ADHD and gum disease. A team in Taiwan recently conducted a nationwide study to explore this connection.
Taiwan has a universal health insurance program, introduced in 1995, that provides medical care to nearly all (99.7%) residents. The Taiwan National Health Research Database collects and oversees all insurance claims, making it an excellent resource for large-scale studies.
The researchers used the database to identify teens aged 12 to 19 with ADHD (diagnosed by a psychiatrist) who had no history of gum disease between 2001 and 2011. These teens made up the ADHD group. They matched each ADHD participant with four teens who didn’t have ADHD or gum disease, creating a control group. The groups were matched by age, gender, enrollment date, family income, place of residence, and other health conditions (like obesity, diabetes, smoking, depression, and substance use).
All diagnoses of gum disease were confirmed by board-certified dentists.
The study included:
The researchers concluded that teens with ADHD have a higher risk of developing gum disease later on, even after accounting for other risk factors like smoking, diabetes, and depression. They stated, “ADHD is an independent risk factor for developing periodontitis.”
_logo%201.svg)
