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Household products

The NPIS continues to study exposures to household products and is at the forefront of global efforts to understand the potential adverse effects, particularly amongst children, of these commonly and widely used chemical products. The NPIS has published data recently on automatic dishwashing products, liquid laundry detergent capsules, automotive screenwashes, oven cleaners and tile and stone floor sealants.


Automatic dishwashing tablets

The traditional tablets for automatic dishwashing machines, which are still used widely, are contained within an external wrapper that requires removal prior to loading the enclosed tablet into the machine. Soluble film automatic dishwashing tablets, unlike their traditional counterparts, require no removal from an outer protective wrapper prior to use. Soluble films used in this way have two main advantages. Firstly, the exact amount of chemicals required for the purpose is delivered once the film dissolves completely in water. Secondly, as there is avoidance of direct contact with the chemicals, the introduction of soluble film products has the potential to improve safety. That being said, the integrity of the soluble film can be compromised and the contents of the tablet can be released prematurely when in contact with moist hands or saliva.

Both traditional and soluble film tablets commonly contain a source of hydrogen peroxide (often as sodium percarbonate) and non-ionic surfactants. Other constituents in some formulations include sodium carbonate, sodium tripolyphosphate and sodium silicate, which reduce water hardness. The pH once dissolved in water is alkaline.


Soluble film automatic dishwashing tablets

The NPIS has recently published the first study to investigate the toxicity of soluble film automatic dishwashing tablets.1 Telephone enquiries to the NPIS regarding these products were analysed retrospectively for the period January 2008 to December 2015.


There were 498 enquiries relating to 488 patients. Almost all exposures occurred in the home (98.4%) and involved children aged five years or younger (92.8%). Exposure occurred mainly as a result of ingestion alone (n=470, 96.3%) or eye contact alone (n=9, 1.8%); exposures involving multiple routes (ingestion with skin or eye contact; n=9, 1.8%) made up the remaining cases.

The majority of patients were asymptomatic following exposure (n=325, 67.4%). The most common feature following ingestion was vomiting which occurred in 121 of 474 cases (25.5%) where clinical data were available. Nausea (n=8, 1.7%) and coughing (n=6, 1.3%) were also reported; three patients developed stomatitis and another five developed a rash where ingestion alone was considered to be the sole route of exposure. Ocular exposure to the tablet contents resulted in blurred vision, eye pain or conjunctivitis in seven of 10 patients.

In conclusion, ingestion of a soluble film automatic dishwashing tablet rarely resulted in clinically significant symptoms, which is surprising given the potential hazard of the ingredients. Hence, it seems probable that the amount of material actually ingested was very small or that most was spat out.


Traditional automatic dishwashing tablets

During 2016/17 the NPIS published the first study in recent decades to investigate the toxicity of traditional automatic dishwashing tablets, and compared them to the soluble film product type.2


There were 503 enquiries relating to 492 patients who had been exposed to a traditional tablet. Most involved children aged five years or less (87.4%). The majority (78.6%) of patients did not develop symptoms after exposure; 21.1% developed minor (poisoning severity score [PSS, see Section 2]) symptoms while one patient developed moderate features. Exposure occurred predominantly as a result of ingestion (n=476, 96.7%); the most common feature in symptomatic patients (n=99, 20.8%) was vomiting (70 [14.7%] cases). Significantly (p<0.0001) more adults (44.9% of 49 adults; 95% CI = 31.9-58.7) were reported with features than children (18.2% of 434; 95% CI = 14.9-22.1). There were five cases of eye contact which resulted in eye pain in two patients and eye irritation in another. Only one of 11 patients exposed dermally developed features (a rash around the mouth).


Comparison between traditional and soluble film exposures

Although exposure to both traditional and soluble film automatic dishwashing tablets rarely produced clinically significant symptoms (PSS ≥ 2), the proportion of patients that became symptomatic following ingestion of a soluble film dishwashing tablet (31.7% of 473 patients; 95% CI=27.7-36.0) was significantly greater (p<0.0001) than that for a traditional tablet (20.9% of 483 patients; 95% CI=17.5-24.8). Vomiting was the most commonly reported feature and occurred significantly (p<0.0001) more frequently amongst patients who had ingested a soluble film tablet (25.5%; 95% CI =21.8-29.6) than a traditional tablet (14.7%; 95% CI =11.8-18.1).

The reasons for the difference in frequency of symptoms after ingestion of soluble film tablets and traditional tablets are not known with certainty, but may relate to the relative hardness of traditional tablets, which children may find difficult to bite. In addition, soluble film tablets containing a liquid may result in greater ingestion of material.


Liquid laundry detergent capsules

The NPIS has published previously detailed data on 2,133 exposures to liquid laundry detergent capsules.3,4,5 Although the majority of patients remain asymptomatic or suffer only minor features (PSS 1), a small proportion develop more severe features such as CNS depression, stridor, pulmonary aspiration and/or airway burns following ingestion, and conjunctivitis leading to corneal ulceration from eye exposure.3,4,5


As a consequence, the International Association for Soaps, Detergents and Maintenance Products (AISE) established a Product Stewardship Programme in Europe, requiring that safety measures be implemented to reduce the visibility of, and restrict access to, these detergent capsules by small children. Implementation occurred in the UK over several months during the first half of 2013 and the NPIS has reported on the impact of the Product Stewardship Programme on the number of exposures and their severity reported to the service.


While there was a significant difference (p=0.0002) between the mean number of annual exposures (469.4) reported between 2008-2012 and the mean number reported between 2014-2015 (403.5), the number of exposures was decreasing steadily prior to implementation of the Programme in 2013, which did not impact this fall from 2013 onwards. In addition, the number of exposures per million units sold was not impacted by the Programme. There was no significant difference (p=0.68) between the mean number of exposures with PSS ≥ 2 reported between 2008-2012 (11.8) and the mean number reported between 2014-2015 (13.0). Although there was a 28.7% decrease between 2010-2012 and 2014-2015 in the number of exposures with PSS ≥ 2 per million units sold, this decrease was not statistically significant (p=0.18).

Thus, there is no evidence that the Product Stewardship Programme has had a beneficial impact on the number of exposures reported to the NPIS or their severity.


Automotive screenwashes

These products may contain ethylene glycol and/or methanol and/or isopropanol, or ethanol alone or in combination with the other ingredients. The concentrations and combinations of each constituent can vary considerably between products. Some products are sold ‘ready-to-use’ off the shelf while others require dilution in water at various ratios dependent on season. The NPIS has recently published the first study to investigate the toxicity of screenwashes.6
There were 295 enquiries involving 255 individual exposures. The majority (n=241, 94.5%) of exposures involved ingestion and 14 of these also involved other routes. Six cases were due to skin contact alone, three to inhalation alone, three to eye contact alone, one to ear exposure alone and another occurred from inhalation and skin contact. Children below five years of age accounted for 26% of all ingestions.
The identity (and therefore composition) of the screenwash was known with certainty in 124 of 241 ingestions and is shown in Table 1. Products included methanol in 106 formulations, isopropanol in 72, ethylene glycol in 38, and ethanol in 104.


Table 1. Composition of screenwash products ingested.


The PSS was known in 235 of 241 cases of ingestion: most patients were asymptomatic (n=169, 71.9%), but 59 (25.1%) developed minor (PSS 1), 6 (2.6%) moderate (PSS 2), and 1 patient severe (PSS 3) features; this patient later died. Nausea (n=10), vomiting (n=11), abdominal pain (n=10), metabolic acidosis (n=8) and raised anion gap (n=8) were the clinical features reported most commonly after ingestion.

In conclusion, most patients (71.9%) ingesting automotive screenwash did not develop features. The implication is that the amount of screenwash ingested was very small.


The concentrations of ethanol in most screenwashes did not appear to impact potential toxicity. Skin and eye exposure produced either no features or only minor toxicity.


Oven cleaners

Oven cleaning products contain corrosive substances, typically sodium or potassium hydroxide.7 The NPIS has published a study to investigate the toxicity of oven cleaners.


Telephone enquiries regarding oven cleaning products were analysed retrospectively for the period January 2009 to December 2015 and 796 enquiries relating to 780 patients were identified. Ninety-six percent of the products involved in the reported exposures contained sodium hydroxide and/or potassium hydroxide. Ingestion alone (n=285) or skin contact alone (n=208) accounted for the majority of cases; inhalation alone (n=101), eye contact alone (n=97), and multiple routes of exposure (n=89) accounted for the remainder. Ninety-five percent of patients exposed by inhalation, 94% exposed dermally and 85% reporting eye exposure, developed features of toxicity. Patients exposed by multiple routes developed symptoms in 70% of cases.


Only 103 of the 285 patients ingested oven cleaner directly, whereas 182 patients ingested food they considered to have been contaminated with oven cleaner. In 100 of the 103 direct ingestions where the features and PSS were known, 56 reported symptoms which were minor in 51 cases. The most common features following ingestion were vomiting (n=26), abdominal pain (n=22) or pharyngitis (n=15). Skin burns (n=91), predominantly involving the hands or arms, occurred in 44% of dermal exposures. Following inhalation, patients frequently developed respiratory features (n=52) including coughing and chest pain/tightness. Eye pain (n=43) and conjunctivitis (n=33) commonly occurred following ocular exposure.


In conclusion, most (71%) patients exposed to an oven cleaner irrespective of the route of exposure developed features of toxicity, though in most cases only minor features developed; moderate or severe features ensued in 4%. Those patients exposed dermally, ophthalmically or by inhalation developed features more frequently (>85%) than those who had ingested a product directly (56%).


Grout, tile and floor stone sealants

These products contain a solvent, a water-repelling agent and, in the case of aerosols, a propellant. The water-repelling agent used is typically a fluoropolymer resin, a silicon based resin, or a combination of both.8


A retrospective analysis was performed of 101 telephone enquiries received between 2009 and 2015 involving 96 exposures. The majority of the exposures (n=88) occurred when the sealant was delivered from an aerosol. Twelve patients were exposed occupationally and the remainder were exposed while using the product at home. Eighty-nine exposures were as a result of inhalation alone, two followed ingestion, three skin contact and one eye contact; another involved inhalation and eye contact.


All 90 patients exposed by inhalation developed clinical features: 31 had a PSS of 1 (minor toxicity), 51 patients had features of moderate toxicity (PSS 2) and 8 were graded as having severe toxicity (PSS 3).The most common features were dyspnoea (n=52; 57.8%; 95% CI=47.0–68.5), chest pain/tightness (n=34; 37.8%; 95% CI=27.2–48.4), coughing (n=27; 30.0%; 95% CI=20.0–40.0) and sinus tachycardia (n=11; 12.2%; 95% CI=4.1–18.2); hypoxaemia was present in 20 (22.2%; 95% CI=13.1–31.4). At the time of the enquiry a chest X-ray had been performed on 15 patients: in eight patients (all of whom were PSS 3) the X-ray was reported as being abnormal and showed bilateral shadowing.


In conclusion, if fluoropolymer-containing sealants are inhaled then clinical features may occur and in a small proportion of cases (9%) these features may be severe.



  1. Day R, Eddleston M, Thomas SHL, Thompson JP, Vale JA. Toxicity of soluble film automatic dishwashing products as reported to the United Kingdom National Poisons Information Service 2008-2015. Clin Toxicol 2016; 54: 862-6.
  2. Day R, Eddleston M, Thomas SHL, Thompson JP, Vale JA. Exposures to traditional automatic dishwashing tablets and a comparison with exposures to soluble film tablets reported to the United Kingdom National Poisons Information Service 2008–2015. Clin Toxicol 2017; 55: 206-12.

  3. Williams H, Bateman DN, Thomas SHL, Thompson JP, Scott RAH, Vale JA. Exposure to liquid detergent capsules: a study undertaken by the UK National Poisons Information Service. Clin Toxicol 2012; 50: 776-80.
  4. Williams H, Jones S, Wood K, Scott RAH, Eddleston M, Thomas SH, et al. Reported toxicity in 1486 liquid detergent capsule exposures to the UK National Poisons Information Service 2009–2012, including their ophthalmic and CNS effects. Clin Toxicol 2014; 52: 136-40.
  5. Day R, Eddleston M, Thomas SHL, Thompson JP, Vale JA. The impact of an international initiative on exposures to liquid laundry detergent capsules reported to the United Kingdom National Poisons Information Service between 2008 and 2015. Clin Toxicol 2017; 55: 213-6.
  6. Day R, Eddleston M, Thomas SHL, Thompson JP, Bradberry SM, Vale JA. Toxicity from automotive screenwashes reported to the United Kingdom National Poisons Information Service (NPIS) from 2012 to 2015. Clin Toxicol 2017; 55: 221-6.
  7. Day RC, Bradberry SM, Sandilands EA, Thomas SHL, Thompson JP, Vale JA. Toxicity resulting from exposure to oven cleaners as reported to the UK National Poisons Information Service (NPIS) from 2009 to 2015. Clin Toxicol 2017. Published online 26/4/17.
  8. Henke D, Campbell A, Bradberry SM, Sandilands EA, Thomas SHL, Thompson JP, et al. Toxicity from fluoropolymer-containing grout, tile and stone floor sealants reported to the UK National Poisons Information Service 2009–2015. Clin Toxicol 2017; 55: 585-8.

Information from recent publications and the NPIS Annual Report 2016/17.


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