DBP Consortium Halogenated active substances and products ARROW REGULATORY LIMITED 6 TH FLOOR CITY GATE EAST TOLL HOUSE HILL NOTTINGHAM NG1 5FS
Contents What are Disinfection By-Products (DBP)? Why are DBPs important to biocide product authorisation? Why form a consortium? What is the consortium doing? Where are we now? 2
What are DBPs? A chemical compound formed by the reaction of a water disinfectant (e.g. chlorine) with a precursor (e.g. natural organic matter) in a water supply. The most commonly known DBPs are those formed with halogens, e.g. chlorine and bromine. Any disinfectant can form DBPs during use, including free radicals and ozone. All natural water sources contain halogens. All potable water contains DBPs 3
What are DBPs? From halogenated disinfectants Trihalometanes (THMs) Haloacetic acids (HAAs) Haloaldehydes Haloacetonitriles Haloamines Chlorate/bromate From ozonation formaldehyde and other aldehydes, carboxylic acids hydrogen peroxide bromate bromomethanes brominated acetic acids brominated acetonitriles and ketones http://www.who.int/water_sanitation_health/dwq/s04.pdf 4
DBPs and the BPR ECHA Guidance Document Volume V: Guidance on Disinfection By- Products. Jan 2017 The disinfection of water with oxidising biocides leads to the formation of by-products (DBPs). According to the Biocides Product Regulation (BPR), the effect of residues should be evaluated in the risk assessment (see e.g. Art. 19,(1)(b)(iii)) and according to the definition in Art. 3,(1)(h), residues include reaction products. A number of known (groups of) DBPs are biologically active, and some are (suspected) carcinogens or mutagens (e.g. chloroform, halogenated methanes, bromate). Moreover, most DBPs are more stable than the biocide itself. Therefore, a risk assessment of DBPs as part of the authorisation of biocidal products is necessary. 5
DBP Guidance Strategy for the evaluation of DBPs - Proposed methodology for assessment Included: Halogenated active substances (oxidisers) Identification of marker substances PT 2, swimming pool disinfectants and PT 11 and 12 preservatives a tentative list of PT for which DBP assessment is relevant It does not exclude: Risk assessment for all PT where DBP may be formed Any other reactive active substance that may form DBP 6
Risk v benefit of disinfection; a balance The risk of waterborne infectious disease is very high when no chlorination is used, and drops sharply to a low value when even minimal levels of chlorination are maintained. We know this on the basis of a century's experience. Morris 1978 the risk of death from pathogens is at least 100 to 1000 times greater than the risk of cancer from disinfection byproducts (DBPs); the risk of illness from pathogens is at least 10 000 to 1 million times greater than the risk of cancer from DBPs; morbidity and mortality rates from pathogens compared with those from DBPs, may be considerably higher in developing countries where the sanitary and health status is not as good; in societies where infant mortality and life expectancy is low, many people would not be expected to live long enough to incur cancer, which also causes much higher differences in risk resulting from exposure to pathogens versus DBPs cited above. Regli et al. (1993) http://www.who.int/water_sanitation_health/dwq/s04.pdf 7
DBP s and the BPR World Health Organisation: Adequate disinfection of drinking-water is the most important priority to assure a safe water supply. BPR Authorisation may be granted if the biocidal product has no immediate or delayed unacceptable effects itself, or as a result of its residues, on the health of humans, including that of vulnerable groups, or animals, directly or through drinking water, food, feed, air, or through other indirect effects (Art 19 1(b) (iii)) A biocidal product may be authorised when the conditions laid down in paragraph 1(b)(iii) and (iv) are not fully met, or may be authorised for making available on the market for use by the general public when the criteria referred to in paragraph 4(c) are met, where not authorising the biocidal product would result in disproportionate negative impacts for society when compared to the risks to human health, animal health or the environment arising from the use of the biocidal product under the conditions laid down in the authorisation. 8
DBP s and the BPR BPR places onus on product manufacturers to identify the application range where risk/benefit is maximised for their products. The BPR cannot force end-users to; use products in accordance with label claim monitor DBP formation and take steps to ensure limits are adhered to. Measurements must be applied via other legal statutes (EU and National). 9
BPR Active substance applications; Substance manufacturers Representative product, often dummy product Default models for risk assessment Generic use patterns Product authorisation Substance manufacturers, formulators or distributors Real products All uses Application dose defined by efficacy studies Deficiencies: Efficacious dose vs DBP formation Lack of incentive for end-user of products to buy-in to product approval scheme 10
Why form a Consortium? Cost Duplication of work Harmonisation/concensus across industry Pooling of knowledge Raising end-user awareness of BPR and it s impact on their business Influencing end-users to become involved, sharing of data 11
DBP Consortium Limited to halogenated active substances and products Open to active substance manufacturers and any company placing halogenated products on the market. Currently 95 members and 11 companies in the process of joining Entry to late-joining members open Steering Committee and Technical Committee Independent experts 12
Scope of work Chlorinated and brominated substances; Sodium and calcium hypochlorite Chlorine Active chlorine and Active bromine Chlorine dioxide Monochloramine Chlorinated isocyanurates; TCCA, NaDCC anhydrous and dihydrate Halohydantoins (e.g. BCDMH) Product Types (halogenated products); PT 1 5 PT 11 and 12 13
Aim A harmonised standard for both chlorinated and brominated biocidal products, i.e. a worst case DBP profile for each disinfectant/preservative use will be identified and assessed for safety. This will lead to the production of a list of label claims (dosing regime and application conditions) that lead to a safe use, in respect to DBP generation, that applicants can reference for their own authorisations. 14
Work Plan Phase 1: Data Collection Phase 2: Expert Assessment Exposure/release data Hazard determination Relevance of marker or groups of DBP Phase 3: Data Gap Assessment Phase 4: Data Generation Phase 5: Risk Assessment and Report on Safe Conditions of Use Report due date: Oct 2018 15
Where are we now? Phase 1: Data Collection Phase 2: Expert Assessment Data Gap Analysis Study planning 16
Sara Kirkham sara@arrowregulatory.com DBP@arrowregulatory.com WEBSITE: ARROWREGULATORY.COM TELEPHONE (+44) (0)1159352243