Perchlorate, nitrate, and thiocyanate: Environmental relevant NIS-inhibitors pollutants and their impact on thyroid function and human health.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing mechanistic and observational literature without systematic review methodology
PubMed 36339434 · doi:10.3389/fendo.2022.995503
What was done
This narrative review synthesized literature on environmental thyroid-disrupting contaminants targeting the sodium-iodide symporter (NIS), the rate-limiting step in thyroid hormone production. It evaluated the mechanisms of action, exposure pathways (food, water, soil, atmosphere, cigarette smoke), and human health consequences of three key NIS-inhibitors: perchlorate, nitrate, and thiocyanate.
What was found
The abstract reports no numerical findings or quantitative metrics. Qualitatively, it states that perchlorate, nitrate, and thiocyanate act as competitive inhibitors of NIS-mediated iodide uptake. It notes that while the clinical impact of human exposure remains highly controversial, reported evidence indicates potential adverse effects on thyroid function, especially in individuals living in iodine-deficient areas.
Why it matters
This review highlights how common environmental contaminants can impair thyroid hormone biosynthesis at the uptake level, identifying iodine-deficient groups as potentially vulnerable populations.
Limits
The abstract provides no quantitative data, exposure thresholds, or effect sizes. As a narrative review rather than a systematic review or meta-analysis, study selection criteria, risk of bias, and total sample sizes across summarized studies are not defined. Human evidence is acknowledged to be controversial.
Cited by
- supports Consuming 150 micrograms of iodine daily is protective to the thyroid gland against thyroid-targeting chemicals.