Assessing the performance of polyphosphate accumulating organisms in a full-scale side-stream enhanced biological phosphorous removal.

Phosphorous (P) removal in wastewater treatment is essential to prevent eutrophication in water bodies. Side-stream enhanced biological phosphorous removal (S2EBPR) is utilized to improve biological P removal by recirculating internal streams within a side-stream reactor to generate biodegradable carbon (C) for polyphosphate accumulating organisms (PAOs). In this study, a full-scale S2EBPR system in a water resource recovery facility (WRRF) was evaluated for 5 months. Batch experiments revealed a strong positive correlation (r = 0.91) between temperature and C consumption rate (3.56-8.18 mg-COD/g-VSS/h) in the system, with temperature ranging from 14°C to 18°C. The anaerobic P-release to COD-uptake ratio decreased from 0.93 to 0.25 mg-P/mg-COD as the temperature increased, suggesting competition between PAOs and other C-consumers, such as heterotrophic microorganisms, to uptake bioavailable C. Microbial community analysis did not show a strong relationship between abundance and activity of PAO in the tested WRRF. An assessment of the economic feasibility was performed to compare the costs and benefits of a full scale WRRF with and without implementation of the S2EBPR technology. The results showed the higher capital costs required for S2EBPR were estimated to be compensated after 5 and 11 years of operation, respectively, compared to chemical precipitation and conventional EBPR. The results from this study can assist in the decision-making process for upgrading a conventional EBPR or chemical P removal process to S2EBPR. PRACTITIONER POINTS: Implementation of S2EBPR presents adaptable configurations, exhibiting advantages over conventional setups in addressing prevalent challenges associated with phosphorous removal. A full-scale S2EBPR WRRF was monitored over 5 months, and activity tests were used to measure the kinetic parameters. The seasonal changes impact the kinetic parameters of PAOs in the S2EBPR process, with elevated temperatures raising the carbon demand. PAOs abundance showed no strong correlation with their activity in the full-scale S2EBPR process in the tested WRRF. Feasibility assessment shows that the benefits from S2EBPR operation can offset upgrading costs from conventional BPR or chemical precipitation.

An update: maternal iodine supplementation, thyroid function tests, and child neurodevelopmental outcomes.

PURPOSE OF REVIEW: The impact of maternal iodine supplementation (MIS) during pregnancy on thyroid function and child neurodevelopmental outcomes in areas of mild-to-moderate iodine deficiency (MMID) remains unclear. RECENT FINDINGS: Despite growing success of salt iodization programs, a 2022 meta-analysis found that 53% of pregnant patients worldwide continue to have insufficient iodine intake during pregnancy. A 2021 randomized controlled trial (RCT) found that MIS in women with mild iodine deficiency led to iodine sufficiency and positive effects on maternal thyroglobulin. A 2021 cohort study of MIS initiated prior to pregnancy was associated with lower thyroid-stimulating hormone (TSH), higher FT3, and FT4. Other cohort studies, however, found that neither salt iodization nor MIS were adequate to meet pregnancy iodine needs. Data have been mixed regarding maternal iodine status and pregnancy outcomes in patients of MMID. Meta-analyses have not shown any clear benefit on infant neurocognitive outcomes with MIS of MMID patients. A 2023 meta-analysis found that the prevalence of excess iodine intake in pregnancy was 52%. SUMMARY: MMID continues to exist during pregnancy. Salt iodization alone may be insufficient to ensure adequate iodine status during pregnancy. There is an absence of high-quality data to support routine MIS in areas of MMID. However, patients with specialized diets (vegan, nondairy, no seafood, noniodized salt, and so on) may be at risk for inadequate iodine status in pregnancy. Excess iodine intake can be detrimental to the fetus and should be avoided during pregnancy.

Iodine-Induced Fetal Hypothyroidism: Diagnosis and Treatment with Intra-Amniotic Levothyroxine.

BACKGROUND: Iodine is necessary for fetal thyroid development. Excess maternal intake of iodine can cause fetal hypothyroidism due to the inability to escape from the Wolff-Chaikoff effect in utero. CASE REPORT: We report a case of fetal hypothyroid goiter secondary to inadvertent excess maternal iodine ingestion from infertility supplements. The fetus was successfully treated with intra-amniotic levothyroxine injections. Serial fetal blood sampling confirmed fetal escape from the Wolff-Chaikoff effect in the mid third trimester. Early hearing test and neurodevelopmental milestones were normal. CONCLUSION: Intra-amniotic treatment of fetal hypothyroidism may decrease the rate of impaired neurodevelopment and sensorineural hearing loss.

Neonatal Serum Phosphorus Levels and Enamel Defects in Very Low Birth Weight Infants.

BACKGROUND: Very low birth weight (VLBW) infants miss out on the period of greatest mineral accretion that occurs during the last trimester of pregnancy and are at higher risk of enamel defects. No studies have well described the relationship between neonatal nutrition and dental outcomes in preterm, VLBW infants. The objective of this study was to assess the differences in nutrition biomarkers, feeding intake, and comorbidities among VLBW infants with and without enamel defects. METHODS: A retrospective chart review of VLBW infants recruited for an ongoing longitudinal dental study between 2007 and 2010 was done. Participants were classified as cases and controls according to the presence/absence of developmental defects of enamel at 8 and/or 18-20 and/or 36 months. Demographics and medical and nutrition data were abstracted from 76 subjects' medical charts. RESULTS: Of the 76 VLBW subjects, 62% had enamel defects (hypoplasia and/or opacity). The only significant variable in the logistic regression analysis was that infants with a 1-mg/dL increase in serum phosphorus levels had a 68% reduction in the odds of having enamel hypoplasia (odds ratio, 0.322; P = .024). CONCLUSION: Neonatal lower serum phosphorus levels are significantly associated with enamel hypoplasia in VLBW infants younger than 3 years.