In total, 746 questionnaires were completed. The response rate was 28% (n = 444) for PHP and 74% (n = 302) for parents.

The overall percentage of correct answers was 68%. It was significantly better in the PHPs’ group compared to the parents’ group (73% vs. 60%, respectively, p < 0.001). Proportions of correct answers to “knowledge” and “beliefs” questions were, respectively, 50 and 57% for parents, and 67 and 85% for PHPs. Rate of “good responses” to “belief” questions were 100% for medical doctor and 71.4% for the other professionals. The global (Figure 1) and specific responses (Figures 2A,B) of the two groups are displayed in the radar chart.

Questions 2, 9, and 14 related to confident in natural products have, respectively, 61, 27, and 45% of good answers in parents’ group and 84, 51, and 65% of good answers in PHPs’ group.

The highest proportion of correct answers was for the question on cosmetic products (question 4): 94% in the parents’ group and 97% in the PHPs’ group (p = NS). The lowest proportion of good answers was for the question on EDs mechanisms of action (question 11): 10% for parents and 11% for professionals (p = NS).

Overall, 66% of parents and 95% of PHPs had already heard of ED. This 66% of parents had a significantly better score than the others (67% vs. 53%, p < 0.001); similarly, this 95% of PHPs had a significantly better score (71% vs. 57%, p = 0.002). However, only 10% of parents and 5% of PHPs reported that they felt sufficiently informed, but they did not have a significantly better score than participants who felt insufficiently informed (Figure 3).

We have observed that 20% of both parents and PHPs systematically screened the product composition, while 15% never screened it. However, this screening was not linked to the proportion of correct answers. By univariate analysis, factors associated with a higher proportion of correct answers for parents were rural location and higher socio-professional categories. For PHPs, these factors were age under 35 years and being a physician.

Information sources were similar between parents and PHPs, the most frequent one being media (television or radio) and the web for 70% of parents and 80% of PHPs; PHPs used mostly “general public” resources. Only 20% of PHPs read scientific papers, and 4% have followed a training on EDs (Figure 4).

Knowledge on EDs is not optimal both for parents and PHPs. The main strengths of this study were a significant number of answers and an evaluation of both parents and PHPs with the same questionnaire. All professionals interacting with parents and children were represented, thus reinforcing the strength of the study. However, PHPs’ knowledge and beliefs were not optimal, and most of them were not trained on EDs.

Our rates of responses are good, close, or better than other reports in the literature, i.e., 11–30% (5, 6, 9). Reasons for obtaining a satisfactory response rate are probably multiple and intricated: the increasing concern about environmental exposures, the availability of researchers for parents with a hand-delivered questionnaire, and the individual mail for the PHPs in a pediatric hospital in which the principal investigator of the study is the senior physician responsible for the pediatric research centre.

Some factors were linked to the profile of “good responders.” For parents these were rural locations and higher socio-professional categories. In rural areas, parents and their children are exposed to specific pollutants such as pesticides and information on this type of environmental exposures is probably more spread. Higher socio-professional categories often have better level of education and better access to information. Furthermore, for the lower socio-professional categories, environmental exposures are not a priority in daily life, even though they are the population most exposed. For professionals, the profile of “good responders” was under 35 years of age and being a doctor. Young professionals are more sensitive to environmental exposures and climate change. Good responses from doctor are linked to better answers to beliefs questions (100% for medical doctor vs. 71.4% for other professionals). Even though they have not received a specific training on EDs, the training provided during their medical training has enabled doctors to acquire a critical mind, which may explain their better responses to beliefs questions.

This single-center study has nevertheless several limitations, by design. As a result, only professionals and parents from patients followed in a tertiary university hospital participated. One may assume that liberal practitioners are more concerned and informed because they receive more questions from parents, with less severely ill children. Also, responders probably felt more concerned with the questions of environmental exposure than parents and PHPs who did not participate. Therefore, we could expect that responses in general populations will be even worse. In addition, we used a non-validated personal questionnaire.

In our study, only 10% of parents and 5% of PHPs considered they are sufficiently informed about EDs. This result is congruent with a previous study reporting that only 11% of perinatal health professionals were sufficiently trained and informed (14). Another French study also found 82% of insufficiently informed professionals (5). The lack of specific training for health professionals on the topic has also been reported in many studies worldwide (10, 14).

The worst answers were about “natural” products. In fact, each question with the term “natural” automatically generated an analysis of “healthy” in parents’ mind but also, however in a lesser extent, in PHPs. As described in human health science publications, instructional messages are not an optimal way to inform both parents and PHPs (15). Dichotomist ideas such as “natural is good” and “industrial is bad” have to be avoided; beliefs must be explored in order to give better messages to the population. Moreover, it may be relevant to analyze in future studies in which state of mind PHPs who are also parents position themselves.

More worrying is the way used by professionals to get information, as already descripted in 2001 (9). There is an urgent need for professionals to be better informed. To achieve this, specific training courses and recommendations from medical scientific societies are required. For example, the International Federation of Gynecology and Obstetric guidelines refer to the presence of heavy metal and EDs in prenatal vitamins and recommends reducing the exposure. These guidelines are easily accessible for the professionals. Conversely, information in the media is often perceived as stressful and incomprehensible by parents (8).

In conclusion, we show that, despite the fact that the risk of environmental exposure and EDs is an increasing concern for parents, the specific knowledge remains scarce both for parents and PHPs. PHPs need to be trained on the topic, so as to provide optimal advice to families.