Peripheral precocious puberty in a 4-month-old girl: role of pesticides?

Concentration levels and risk assessment of organochlorine and organophosphate pesticide residue in selected cereals and legumes sold in Anambra State, south-eastern Nigeria

The levels of organochlorine and organophosphate pesticide residues in selected cereal crops (beans, cowpea, millet, maize, sorghum, and rice) purchased from major markets in Anambra, south-eastern Nigeria, were assessed and compared with established MRLs. The QuEChERS (quick, easy, cheap, effective, rugged, and safe) method was used for extraction and clean-up of pesticide residues. Thereafter detection and quantification were done using GC/MS. The result reveals that the analysed grain samples contained some organochlorine pesticides and organophosphates. The organochlorine was most dominant followed by the organophosphates. Organochlorine pesticide residues varied from 0.048 to 0.298 mg/kg in beans, BDL to 0.398 mg/kg in cowpea, 0.018–0.337 mg/kg in maize, 0.023–0.375 mg/kg in millet, 0.058–0.415 mg/kg in sorghum and 0.045–0.442 mg/kg in rice while organophosphate pesticide residue varied from BDL to 0.315 mg/kg in beans, BDL to 0.113 mg/kg in cowpea, BDL to 0.228 mg/kg in maize, BDL to 0.253 mg/kg in millet, BDL to 0.218 mg/kg in sorghum and BDL to 2.1 35 mg/kg in rice. Highest concentration of endosulphan II (0.442 mg/kg) was detected in rice, followed by aldrin (0.415 mg kg−1) in sorghum and endosulphan II (0.40 mg/kg) in sorghum. The pesticide toxicity index (PTI) was above one (1), whereas health index (HI) was less than one (1) and cancer risk were within USEPA reference guideline for crops indicating children will have greater health effect than adults. Hence, strict monitoring and control of pesticide residues in agricultural products is advocated.

Oestrogenic Activity in Girls with Signs of Precocious Puberty as Exposure Biomarker to Endocrine Disrupting Chemicals: A Pilot Study

The relationship between endocrine disrupting chemical (EDC) exposure and Precocious Puberty (PP) was investigated in this pilot study, involving girls with signs of PP (P) and pre-pubertal girls (C). Risk factors for PP were assessed through questionnaires, while 17β-oestradiol (E2) levels and oestrogenic activity were quantified on sera. The oestrogenic activity, expressed as E2 equivalent concentration (EEQ), was applied as EDC exposure biomarker. Questionnaires showed a low EDC knowledge, a high EDC exposure, and a potential relationship between some habits at risk for EDC exposure and PP. EEQs were similar between C and P; however, they were significantly higher in girls living in an urban environment than in girls living in a rural environment, suggesting a potential higher EDC exposure in cities. The results of this pilot study highlighted the need to raise awareness on EDCs and can be considered a starting point to clarify the relationship between EDC exposure and PP.

[Environmental endocrine disruptors and fertility]

Endocrine disruptor chemicals (EDCs) are ubiquitous contaminants in the environment, wildlife, and humans. During the last 20 years, several epidemiological, clinical and experimental studies have demonstrated the role of EDCs on the reduction of male and female fertility. The concept of foetal origins of adult disease is particularly topical in the field of reproduction. Moreover, exposure to EDCs during pregnancy has been shown to influence epigenetic programming of endocrine signalling and other important physiological pathways, and provided the basis for multi- and transgenerational transmission of adult diseases. However, the large panel of EDCs simultaneously present in the air, sol and water makes the quantification of human exposition still a challenge. Gas chromatography coupled with mass spectrometry, the measurement of total plasmatic hormonal bioactivity on stably transfected cell lines as well as the EDC analysis in hair samples are useful methods of evaluation. More recently, microRNAs analysis offers a new perspective in the comprehension of the mechanisms behind the modulation of cellular response to foetal or post-natal exposure to EDCs. They will help researchers and clinicians in identifying EDCs exposition markers and new therapeutic approaches in the future.

Estrogenic activity of biological samples as a biomarker

Biological assays can evaluate the cumulative effect of a mixture, considering synergistic/antagonistic interactions and effects of unknown/unconsidered compounds. Therefore, their application could increase in the next years also to analyse biological samples. The aim of this review is to discuss the methodological approach and the application of estrogenic activity assays in human biological samples. 75 research articles were analysed and divided according to whether they used these assays: i) to quantify the level of estrogens and/or as a biomarker of estrogenic status ii) as a biomarker of exposure to endocrine disrupting chemicals (EDCs). For the first purpose, some authors extracted biological samples while others tested them directly without any treatment. The study of these methodologies outlined that the methodology applied influenced the specificity of analysis. The estrogenic activity biomarker was used to analyse physiological variations of estrogens, pediatric diseases, hormone-dependent diseases and estrogen suppression/enhancement after pharmaceutical treatments. For the second purpose, some authors extracted samples while others tested them directly, some authors divided endogenous estrogens from xenoestrogens while others tested samples without separation. The analysis of these methodologies outlined some limitations related to the efficiency of extraction and the incorrect separation of some compounds. The studies which applied this EDC biomarker showed that it was correlated with some EDCs, it varied according to the exposure of the population and it allowed the identification of some relationships between EDC exposure and breast cancer, type 1 diabetes and adverse health effects on children. In conclusion, the estrogenic activity of biological samples can be a useful tool: to quantify low levels of 17β-estradiol, to assess the combined effect of endogenous estrogens and xenoestrogens, to estimate the estrogenic status providing considerable insight into physiological or pathological conditions, to evaluate EDC presence implementing the existing knowledge about EDC exposure and adverse health effects.

Morning basal luteinizing hormone, a good screening tool for diagnosing central precocious puberty

PURPOSE

The standard method used to diagnose central precocious puberty (CPP) is the gonadotropin releasing hormone stimulation test (GnRHST). However, this test is inconvenient for children because it is time-consuming and requires multiple samples. This study aimed to determine the reliability of morning unstimulated luteinizing hormone (mLH) level when screening for CPP, with an emphasis on the influence of diurnal variation.

METHODS

This study included 160 girls with signs of early puberty (SMR 2) under 8 years of age. They were classified as CPP or non-CPP based on their standard GnRHST. The auxological, biochemical, and hormonal characteristics of subjects were retrospectively evaluated. The prognostic value of single morning unstimulated gonadotropin level was examined for use in CPP screening.

RESULTS

Of 160 patients, 121 (75.6%) presented with CPP, and 39 (24.4%) were determined to be prepubertal. The mLH/mFSH (morning unstimulated follicular stimulating hormone) ratio showed significant differences between the 2 groups (P<0.001). The mLH was correlated with GnRHST variables (r=0.532, P<0.001). The mLH cutoff point when screening for CPP was 0.22 IU/L, which had sensitivity and specificity of 69.4% and 82.1%, respectively. In regression analysis, bone age (BA) (odds ratio [OR], 1.018; 95% confidence interval [CI], 0.967-1.071; P=0.506) and body mass index (BMI) (OR, 0.874; 95% CI, 0.583-1.310; P=0.515) were not significant predictors. The mLH≥0.22 IU/L group (OR, 9.596; 95% CI, 3.853-23.900; P<0.001) was highly suggestive of CPP.

CONCLUSION

In this study, single morning unstimulated luteinizing hormone had clinical efficacy for CPP screening, but BA advanced over chronological age and BMI was not useful for CPP screening.

Low doses of bioherbicide favour prion aggregation and propagation in vivo

Public concerns over the use of synthetic pesticides are growing since many studies have shown their impact on human health. A new environmental movement in occidental countries promoting an organic agriculture favours the rebirth of botanical pesticides. These products confer an effective alternative to chemical pesticides such as glyphosate. Among the biopesticides, the α-terthienyls found in the roots of Tagetes species, are powerful broad-spectrum pesticides. We found that an α-terthienyl analogue with herbicidal properties, called A6, triggers resistant SDS oligomers of the pathogenic prion protein PrP^Sc (rSDS-PrP^Sc) in cells. Our main question is to determine if we can induce those rSDS-PrP^Sc oligomers in vitro and in vivo, and their impact on prion aggregation and propagation. Using wild-type mice challenged with prions, we showed that A6 accelerates or slows down prion disease depending on the concentration used. At 5 mg/kg, A6 is worsening the pathology with a faster accumulation of PrP^Sc, reminiscent to soluble toxic rSDS-PrP^Sc oligomers. In contrast, at 10 and 20 mg/kg of A6, prion disease occurred later, with less PrP^Sc deposits and with rSDS-PrP^Sc oligomers in the brain reminiscent to non-toxic aggregates. Our results are bringing new openings regarding the impact of biopesticides in prion and prion-like diseases.

Neurotoxicity of a Biopesticide Analog on Zebrafish Larvae at Nanomolar Concentrations

Despite the ever-increasing role of pesticides in modern agriculture, their deleterious effects are still underexplored. Here we examine the effect of A6, a pesticide derived from the naturally-occurring α-terthienyl, and structurally related to the endocrine disrupting pesticides anilinopyrimidines, on living zebrafish larvae. We show that both A6 and an anilinopyrimidine, cyprodinyl, decrease larval survival and affect central neurons at micromolar concentrations. Focusing on a superficial and easily observable sensory system, the lateral line system, we found that defects in axonal and sensory cell regeneration can be observed at much lower doses, in the nanomolar range. We also show that A6 accumulates preferentially in lateral line neurons and hair cells. We examined whether A6 affects the expression of putative target genes, and found that genes involved in apoptosis/cell proliferation are down-regulated, as well as genes reflecting estrogen receptor activation, consistent with previous reports that anilinopyrimidines act as endocrine disruptors. On the other hand, canonical targets of endocrine signaling are not affected, suggesting that the neurotoxic effect of A6 may be due to the binding of this compound to a recently identified, neuron-specific estrogen receptor.

Organochlorine pesticides and female puberty in South Kazakhstan

The purpose of the study was to assess the puberty of females living in cotton-growing regions of South Kazakhstan, where organochlorine pesticides are widely used. The physical growth and sexual development were assessed; organochlorine pesticides, gonadotropic and steroid hormones, as well as insulin-like growth factor 1 in the peripheral blood were determined. 524 females (adolescents aged 10-17) were examined. They were divided into 2 groups, depending on their place of residence. The clinical research included the assessment of physical and sexual development. All examined females lived in rural areas, i.e. they were comparable in terms of social, welfare, and climatographic factors. A high concentration of organochlorine pesticides (lindane-18.51±0.16mg/l, dieldrin-169.16±3.13mg/l, DDT-177.78±2.71mg/l, endrin-37.57±0.9mg/l) in the blood of females living in regions exposed to pesticides compared to their peers (4.05±0.41mg/l, 30.8±3.7mg/l, 109.7±2.58mg/l, 4.85±0.69mg/l respectively) was found (p<0.001). The physical and sexual development of such females was delayed. The research established a correlation between the concentration of pesticides and the endocrine status, as well as with the insulin-like growth factor 1. This shows the adverse effect of organochlorine pesticides on the development of the female reproductive system during puberty.

Association of PAEs with Precocious Puberty in Children: A Systematic Review and Meta-Analysis

Background: Precocious puberty (PP) currently affects 1 in 5000 children and is 10 times more common in girls. Existing studies have tried to detect an association between phathalic acid esters (PAEs) and PP, but the results did not reach a consensus. Objective: To estimate the association between PAEs and children with PP based on current evidence. Methods: Databases including PubMed (1978 to March 2015), OVID (1946 to March 2015), Web of Science (1970 to March 2015), EBSCO (1976 to March 2015), CNKI (1979 to March 2015), WANFANG DATA (1987 to March 2015), CBM (1978 to March 2015) and CQVIP (1989 to March 2015) were searched to identify all case-control studies that determined the exposure and concentration of PAEs and their metabolites in children with PP. Meta-analysis of the pooled standard mean difference (SMD) and odds ratio (OR) with 95% confidence intervals (CI) were calculated. Results: A total of 14 studies involving 2223 subjects were finally included. The pooled estimates showed that PP was associated with di-(2-ethylhexyl)-phthalate (DEHP) exposure (OR: 3.90, 95% CI: 2.77 to 5.49). Besides, the concentration of DEHP (SMD: 1.73, 95% CI: 0.54 to 2.91) and di-n-butyl phthalate (DBP) (SMD: 4.31, 95% CI: 2.67 to 5.95) in the PP group were significantly higher than those in the control group, respectively, while no difference was detected between case and control groups in either serum or urinary concentration of mono-(2-ethylhexyl)-phthalate (MEHP), monobutyl phthalate (MBP), mono(2-ethyl-5-oxohexyl) phthalate(MEOHP), mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), monomethyl phthalate (MMP), monobenzyl phthalate (MBzP) or monoethyl phthalate (MEP). Conclusions: Exposure of DEHP and DBP might be associated with PP risk for girls, however, there is no evidence to show an association between the exposure to most PAE metabolites and PP. Given the moderate strength of the results, well-designed cohort studies with large sample size should be performed in future.

Increased serum estrogenic bioactivity in girls with premature thelarche: a marker of environmental pollutant exposure?

The aim of the work was to investigate the pathophysiology of isolated premature thelarche (IPT) by determining the impact of pre/postnatal exposure to endocrine disrupting chemicals (EDCs) through evaluation of total serum estrogenic bioactivity (EBA). The pathophysiology remains elusive, although recent investigations suggested the role of EDCs in premature female breast development. We investigated 15 girls with IPT. Plasma estradiol, follicle-stimulating hormone, and luteinizing hormone were measured in basal state and after gonadotropin-releasing hormone testing; bone age and uterine length were also assessed for all patients. Total EBA of patient serum was analyzed with an ultrasensitive bioassay that we previously developed and compared with that of 18 age-matched control girls. Parents were interviewed about their environmental/occupational exposure to EDCs during the patient's prenatal/postnatal life. Nine families reported parental occupational/environmental EDCs exposure during prenatal/postnatal patient life; the mean total EBA found in these 9 IPT girls was significantly elevated (12.31 ± 6.64 pg/mL) in comparison with that of the 6 patients without exposure (2.53 ± 0.73 pg/mL) and the 18 age-matched controls (3.53 ± 2.23 pg/mL; p < 0.01). The significant increase in total EBA in these 9 girls with IPT suggests that premature female breast development may be related in some cases to higher pre/postnatal contamination by EDCs.