Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. 
Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. What was reviewed?
This comprehensive toxicological profile for tin and tin compounds, prepared by the Agency for Toxic Substances and Disease Registry (ATSDR), systematically reviews and characterizes the toxicological and adverse health effects information for metallic tin, inorganic tin compounds, and organotin compounds. The review synthesizes and interprets available toxicologic information and epidemiologic evaluations from both human and animal studies to ascertain levels of significant human exposure and the associated acute, subacute, and chronic health effects. It covers chemical and physical properties, production, potential for human exposure, and relevant governmental regulations, serving as a definitive reference for health professionals and risk assessors.
Who was reviewed?
The profile consolidates and assesses data from a wide array of human case reports, occupational exposure studies, and controlled animal investigations. Human data primarily come from cases of accidental or occupational exposure to tin dusts, fumes, or compounds, as well as from populations consuming tin-contaminated food. Animal studies, which form the bulk of the toxicological database, involve various species, predominantly rodents (rats, mice), but also rabbits, guinea pigs, hamsters, gerbils, and non-human primates, exposed via inhalation, oral, and dermal routes to evaluate the full spectrum of potential health effects, including systemic, immunological, neurological, reproductive, developmental, and carcinogenic outcomes.
Most important findings
| Critical Point | Details |
|---|---|
| Differential Toxicity | Inorganic tin compounds exhibit low toxicity, primarily causing gastrointestinal upset and anemia at high doses, while organotin compounds are significantly more toxic, with effects varying by specific compound (e.g., trimethyltin is neurotoxic, tributyltin is immunotoxic). |
| Primary Exposure Route | For the general population, the most significant exposure pathway to inorganic tin is through the consumption of canned foods, where tin can leach from the container. Exposure to organotins can occur from contaminated seafood, leaching from PVC pipes, or contact with consumer products containing these compounds. |
| Hematological Effects | High oral doses of inorganic tin can induce anemia in animals, an effect that is exacerbated by concurrent deficiencies of essential minerals like copper and iron, highlighting the importance of nutritional status in risk assessment. |
| Neurological Effects | Triethyltin and trimethyltin are potent neurotoxins. Human exposures have led to severe, sometimes permanent, neurological damage, including brain edema, neuronal necrosis, and persistent cognitive and behavioral deficits. |
| Immunological Effects | Several organotins, particularly tributyltin and dibutyltin compounds, are immunotoxic, causing thymus atrophy, lymphocyte depletion, and impaired immune function in animals at relatively low exposure levels. |
| Reproductive/Developmental Effects | Animal studies show that organotins like tributyltin, triphenyltin, and dibutyltin can cause pregnancy failure, fetal resorptions, and malformations (e.g., cleft palate), though it is often unclear if these effects occur independently of maternal toxicity. |
| Minimal Risk Levels (MRLs) | The profile establishes oral MRLs for specific tin compounds, including 0.3 mg/kg/day for inorganic tin (intermediate-duration), 0.005 mg/kg/day for dibutyltin dichloride, and 0.0003 mg/kg/day for tributyltin oxide (intermediate- and chronic-duration), providing critical health guidance values. |
| Regulatory Limits | OSHA has set workplace exposure limits of 2 mg/m³ for inorganic tin compounds and 0.1 mg/m³ for organotins. The FDA regulates the use of certain organotins in food packaging and sets limits for tin as a food additive. |
Key implications
The ATSDR profile necessitates that a heavy metal certification program for tin must rigorously distinguish between inorganic and organic forms due to their vastly different toxicological profiles. Certification should mandate stringent testing for immunotoxic and neurotoxic organotins like tributyltin and trimethyltin in consumer products, especially those involving plastics, coatings, and materials that may leach into food or water. For inorganic tin, while less toxic, certification should enforce limits in food packaging to prevent gastrointestinal distress and consider nutritional status, particularly iron and copper levels, in risk assessments. A significant research gap exists regarding the long-term, low-level exposure effects of organotins on human neurodevelopment and immune function, which should be prioritized. Practical recommendations include promoting alternatives to organotin-based stabilizers and antifouling paints and clearly labeling products that may contain these compounds to mitigate public exposure.
Citation
Toxicological Profile for Tin and Tin Compounds. Atlanta (GA): Agency for Toxic Substances and Disease Registry (US); 2005 Aug.
Heavy metals are high-density elements that accumulate in the body and environment, disrupting biological processes. Lead, cadmium, arsenic, mercury, nickel, tin, aluminum, and chromium are of greatest concern due to persistence, bioaccumulation, and health risks, making them central to the HMTC program’s safety standards.
