Girl or boy? Prenatal lead, cadmium and mercury exposure and the secondary sex ratio in the ALSPAC study

AbstractThe aim of this study was to evaluate the effect of prenatal exposure to lead, cadmium and mercury levels on the secondary sex ratio. Whole blood samples were collected from pregnant women enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) study at a median gestational age of 11 weeks and were analyzed for lead, cadmium and mercury. Regression analysis was used to identify associations between maternal lead, cadmium and mercury levels and the secondary sex ratio with adjustment for confounders. There was no evidence for associations between maternal lead, cadmium or mercury levels and the secondary sex ratio in this sample. It appears unlikely that alterations in the secondary sex ratio are influenced by exposure to heavy metals, but further work should be done in large cohorts in other countries to confirm these findings

Intake of game birds in the UK:assessment of the contribution to the dietary intake of lead by women of childbearing age and children

AbstractObjectiveConcern has recently been expressed about Pb levels in Pb-shot game meat. Our aim was to determine the consumption of game birds in a representative sample population in the UK, and in children and women of childbearing age in particular.DesignPopulation-based cross-sectional cohort study. Data from 4 d diet diaries from the UK National Diet and Nutrition Survey (NDNS; 2008–2010) were extracted to analyse data on game bird consumption in the sample population, in women of childbearing age (15–45 years old) and in children ≤6 years old.SettingHome-based study in representative areas of the UK.SubjectsParticipants in the NDNS (2008–2010; n 2126, age 1·5 to &gt;65 years).ResultsFifty-eight participants (2·7 %) reported eating game birds. The mean intake was 19·5 (sd 18·1) g/d (median 15·6, range 1·3–92·9 g/d). In women of childbearing age (15–45 years), 11/383 (2·9 %) reported eating game birds, with a mean intake of 22·4 (sd 25·8) g/d (median 15·6, range 2·0–92·9 g/d). In children aged ≤6 years old, 3/342 (0·9 %) were reported as eating game birds, with a mean intake of 6·8 (sd 9·7) g/d (median 2·4, range 1·3–23·2 g/d).ConclusionsThe prevalence of consumption of game birds by women of childbearing age and children ≤6 years old was relatively low and intakes were small. However, any exposure to Pb in these two groups is undesirable. As are uncertainties about the ability of the diet diary method to capture the consumption of food items that are infrequently consumed, alternative methods of capturing these data should be used in future studies.</jats:sec

Psychosocial and educational outcomes of weight faltering in infancy in ALSPAC

OBJECTIVES: To investigate whether infants with weight faltering have impaired psychosocial and educational outcomes in later childhood. DESIGN: Follow-up of infants with weight faltering in a large UK cohort study. SETTING: The Avon Longitudinal Study of Parents and Children (ALSPAC). PARTICIPANTS: 11 534 term infants from ALSPAC with complete weight records. Weight gain (conditional on initial weight) was calculated for three periods: from birth to 8 weeks, 8 weeks to 9 months, and birth to 9 months. Cases of weight faltering were defined as those infants with a conditional weight gain below the 5th centile, and these were compared with the rest of the cohort as the control group. OUTCOMES: Between 6 and 11 years, social, emotional and behavioural development was measured by direct assessment of the children and parental and teacher report. Educational outcomes included Standardised Assessment Test results at 7 and 11 years and Special Educational Needs status at age 11. RESULTS: Differences seen on univariate analysis in attention, non-verbal accuracy, educational attainment and special educational needs became non-significant after adjustment for confounding. Children with weight faltering in infancy did not differ from controls on any measures of self-esteem, peer relationships, experience of bullying, social cognition, antisocial activities, anxiety, depression or behavioural problems. CONCLUSIONS: Weight faltering in early infancy was associated with poorer educational outcomes in later childhood, but these associations were explained by confounding. The subsequent psychosocial development of infants with slow weight gain was not different from that of their peers

Low level lead exposure and pregnancy outcomes:dose–response relationships

BACKGROUND: National and international guidelines on safe levels for blood Pb in pregnancy focus on a threshold above which exposure is of concern. However, it has recently been suggested that the decrease in birth weight per unit increase in blood Pb is actually greater at lower than at higher concentrations of Pb without evidence of a lower threshold of effect. Our aim was to investigate whether there was evidence for a differential effect of maternal Pb levels on birth outcomes and/or a threshold value for effects. METHODS: Blood samples from pregnant women enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) were analysed. Data collected on the infants included anthropometric variables. We fitted adjusted multivariable fractional polynomial models for birth outcomes. RESULTS: Adjusted models that assumed a linear relationship between untransformed blood Pb and the outcomes provided the best fit: an increase of 1 µg/dl was associated with changes in birth weight of −9.93 (95 % CI −20.27, 0.41) g, head circumference −0.03 (95 % CI −0.06, 0.00) cm and crown–heel length −0.05 (95 % CI −0.10, 0.00) cm. CONCLUSION: There was no evidence in this study to suggest a supralinear dose–response relationship or a lower threshold for the effect of maternal blood Pb on birth outcomes. This has implications for consideration of national and international guidelines on levels of concern in pregnancy. Exposure to Pb should be kept as low as possible during pregnancy to minimise adverse outcomes

Impact of co-occurring hearing and visual difficulties in childhood on educational outcomes:a longitudinal cohort study

Background: Mild hearing and visual difficulties are common in childhood, and both may have implications for educational achievement. However, the impact of co-occurring common hearing and visual difficulties in childhood is not known. Objective: To determine the prevalence and impact of co-occurring common hearing and visual difficulties of childhood on educational outcomes in primary and secondary school. Methods: The sample was drawn from the Avon Longitudinal Study of Parents and Children, a longitudinal birth cohort study in England. The exposures were hearing and visual difficulties at age 7 (defined as conductive hearing loss or otitis media with effusion, and amblyopia, strabismus or reduced visual acuity, respectively). The outcomes measured were achievement of level 4 or above at Key Stage 2 (KS2) in English, Maths and Science, respectively, at age 11, and attainment of five or more General Certificate of Secondary Education (GCSEs) at grades A*-C at age 16. Multiple logistic regression models assessed the relationship between hearing and visual difficulties and educational outcomes, adjusting for potential confounding factors. Results: 2909 children were included in the study; 261 had hearing difficulties, 189 had visual difficulties and 14 children had co-occurring hearing and visual difficulties. Children with co-occurring hearing and visual difficulties were less likely to achieve the national target at KS2 compared with children with normal hearing and vision, even after adjustment for confounding factors (OR 0.30, CI 0.15 to 0.61 for KS2 English). Differences in IQ, behaviour, attention and social cognition did not account for this relationship. The impact of co-occurring hearing and visual difficulties on GCSE results was explained largely by poor performance at KS2. Conclusions: Co-occurring hearing and visual difficulties in childhood have an enduring negative impact on educational outcomes. Identification of affected children and early intervention in primary school is essential

Balance ability in 7- and 10-year-old children:associations with prenatal lead and cadmium exposure and with blood lead levels in childhood in a prospective birth cohort study

OBJECTIVES: Most studies reporting evidence of adverse effects of lead and cadmium on the ability to balance have been conducted in high-exposure groups or have included adults. The effects of prenatal exposure have not been well studied, nor have the effects in children been directly studied. The aim of the study was to identify the associations of lead (in utero and in childhood) and cadmium (in utero) exposure with the ability to balance in children aged 7 and 10 years. DESIGN: Prospective birth cohort study. PARTICIPANTS: Maternal blood lead (n=4285) and cadmium (n=4286) levels were measured by inductively coupled plasma mass spectrometry in women enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) during pregnancy. Child lead levels were measured in a subsample of 582 of ALSPAC children at age 30 months. MAIN OUTCOME MEASURES: Children completed a heel-to-toe walking test at 7 years. At 10 years, the children underwent clinical tests of static and dynamic balance. Statistical analysis using SPSS V.19 included logistic regression modelling, comparing categories of ≥ 5 vs <5 µg/dL for lead, and ≥ 1 vs <1 µg/L for cadmium. RESULTS: Balance at age 7 years was not associated with elevated in utero lead or cadmium exposure (adjusted OR for balance dysfunction: Pb 1.01 (95% CI 0.95 to 1.01), n=1732; Cd 0.95 (0.77 to 1.20), n=1734), or with elevated child blood lead level at age 30 months (adjusted OR 0.98 (0.92 to 1.05), n=354). Similarly, neither measures of static nor dynamic balance at age 10 years were associated with in utero lead or cadmium exposure, or child lead level. CONCLUSIONS: These findings do not provide any evidence of an association of prenatal exposure to lead or cadmium, or lead levels in childhood, on balance ability in children. Confirmation in other cohorts is needed

An evaluation of the efficacy and impact of a clinical prediction tool to identify maltreatment associated with children’s burns

Background An estimated 10%–24% of children attending emergency departments with a burn are maltreated. Objective To test whether a clinical prediction tool (Burns Risk assessment for Neglect or abuse Tool; BuRN-Tool) improved the recognition of maltreatment and increased the referral of high-risk children to safeguarding services for assessment. Methods A prospective study of children presenting with burns to four UK hospitals (2015–2018), each centre providing a minimum of 200 cases before and after the introduction of the BuRN-Tool. The proportions of children referred to safeguarding services were compared preintervention and postintervention, and the relationship between referral and the recommended cut-off for concern (BuRN-Tool score (BT-score) ≥3) was explored. Results The sample was 2443 children (median age 2 years). Nurses and junior doctors mainly completed the BuRN-Tool, and a BT-score was available for 90.8% of cases. After intervention, 28.4% (334/1174) had a BT-score ≥3 and were nearly five times more likely to be discussed with a senior clinician than those with a BT-score <3 (65.3% vs 13.4%, p<0.001). There was no overall difference in the proportion of safeguarding referrals preintervention and postintervention. After intervention, the proportion of referrals for safeguarding concerns was greater when the BT-score was ≥3 (p=0.05) but not for scores <3 (p=0.60). A BT-score of 3 as a cut-off for referral had a sensitivity of 72.1, a specificity of 82.7 and a positive likelihood ratio of 4.2. Conclusions A BT-score ≥3 encouraged discussion of cases of concern with senior colleagues and increased the referral of <5 year-olds with safeguarding concerns to children’s social care