Poisons centres (PC) play an increasing role in toxicosurveillance, i.e. the detection of new poisoning risks and trends. If a signal indicating a new poisoning risk is detected there is often need for quantitative evaluation. A simple algorithm was developed and applied to describe and compare poisoning risks of products based on PC exposure data.
All human exposure cases in the GIZ-Nord database in 2011 were classified for poisoning severity according to the Poisoning Severity Score. All agents related to these cases were categorised based on their intended uses according to the Toxikologischer Dokumentations- und Informationsverbund (TDI) agent category system.
ToxIndex was defined as the sum of all cases classified as lethal, severe or moderate divided by the number of all exposure cases. Subsets of cases selected by product category and patient age were analysed.
number of all cases classified as lethal, severe or moderate
ToxIndex = –––––––––––––––––––––––––––––––––––––––––––––––––––––––
number of all exposure cases related to a selected agent group
In total, 31,154 exposure cases were included. The ToxIndex for all exposures was calculated to be 13%. ToxIndex for selected product groups are listed in Table 1. Drugs of abuse are the most risky product group, while exposures to homeopathic drugs very rarely lead to more than minor symptoms.
Table 1: ToxIndex calculated for selected exposures reported to GIZ-Nord Poisons Center in 2011
|Agent category||Total number of exposures||ToxIndex for 0–17 year old patients||ToxIndex for patients older than 17 years||Overall ToxIndex|
|All agents||31154||27 %||3 %||13 %|
|Drugs of abuse||560||51 %||39 %||48 %|
|All medical drugs||11746||35 %||5 %||23 %|
|Animals||280||28 %||7 %||19 %|
|Biocides and plant protection products||938||16 %||3 %||9 %|
|Palnts||3399||14 %||2 %||3 %|
|Cosmetic Products||1721||6 %||1 %||2 %|
|Homeopathic drugs||224||6 %||1 %||1 %|
ToxIndex, i.e. the proportion of more-than-minor-grade poisoning cases of all exposures, is a simple tool to identify and compare poisoning risks in product groups. Based on ToxIndex for wider product groups (as presented here) the poisoning risk for selected subgroups or single products can also be evaluated: ToxIndex for liquid laundry detergent capsules was 13% compared to 3% for all laundry detergents.
Toxindex, earlier called IntoxIndex, was used in the past for analysing poisoning risks of different product groups by GIZ-Nord Poisons Center.
Furthermore, scoring systems using the ToxIndex defintion but was not named was used for other analyses by poisons centres and authorities.
ToxIndex was presented and recommended as a tool with a broad field of applications at the EAPCCT Congress in Copenhagen 2013:
Desel H (2013) ToxIndex – a tool to compare population poisoning risks for toxic agents. Clin Tox 51, 302