Mapping and health assessment of chemical substances in shoe care products
1 Introduction
The Danish Toxicology Centre (DTC) has been asked to carry out the project ”Mapping and health evaluation of chemical substances in shoe care products” as offered in project proposal of 9 January 2004 from the Danish Environmental Protection Agency (EPA).
Clothes and footwear make up 4-10% of the total consumption of a Danish household [1] (in costs). Every Dane buys an average of 4 pairs of shoes per year and in order for footwear to last and to look nice it is necessary to use shoe care products such as shoe polish, leather grease, cleaning agents and impregnation products. There are many internet sites that deal with the care of footwear including a shoe care guide containing information about how to maintain and care for shoes made from various types of leather [2].
Shoe care products may contain substances that are problematic to humans and the environment. The EPA proposal for the project ”Mapping and health evaluation of chemical substances in shoe care agents” mentions that it is assumed that shoe care agents may contain persistent, bio-acccumulative and toxic substances (PBT substances), e.g. problematic dyes and PFOS compounds. Certain azo-dyes are thus covered by the Danish Working Environment Authority's (DWEA) Order on Cancer [3], ban on import, sale and use [4] and are in addition included on the EPA list of unwanted substances [5]. PFOS substances are included on the List of unwanted substances.
From Environmental Project no. 691 ”Kortlægning af perfluoroktanylsulfonat og lignende stoffer i forbrugerprodukter - fase 2” (Mapping of perflouroctaneyl sulphonate and similar substances in consumer products – phase 2) it can be seen that PFOS compounds are found in leather impregnation products (5 products) and leather care products in the form of shoe polish. Based on data from the Product Register, the report estimates that the amount of PFOS compounds sold per year as ingredients in products comprises approximately 2,400 kg in leather impregnation agents and approximately 15 kg in shoe polishes, respectively.
The PFOS substance load from shoe polish is thus significantly lower than the load from the impregnation agents, but unlike the impregnation agents which are usually not coloured, shoe polish can be purchased in many colours in addition to the traditional black. As PBT dyes are used for i.a. colouration of leather, it is not unusual for shoe polish (particularly certain colour nuances) to contain these substances.
In addition to the above-mentioned groups of problematic substances, shoe care products may contain a number of other compounds that can be potentially harmful to humans and/or the environment. The National Institute of Health in the USA [6] has created a database containing more than 4000 household products on the American market. The database provides access to safety data sheets and information on certain ingredients. In the database, 4 products have been found that can be considered shoe care products (Jump Shoe Cleaning Gel, Jump Shoe Conditioning Liquid, Kiwi Shoe White, Kiwi Scuff Magic, Black). According to the information in the database, the products contain substances such as: isopropyl alcohol and ethylenglycol (solvents), titan dioxide and carbon black (dyes) and the preservatives methylchlorisothiazolinon and methylisothiazolon (kathon).
A search in the Nordic product registers' database (the SPIN-database) for the user codes corresponding to leather impregnation products (I0510) and shoe polish (P1015) only provided limited information on ingredients (water, isopropyl alcohol, ethylacetate, butylacetate) due to the confidentiality regulations. However, a search for the NACE-code [7] ”B31 Impregnation materials” listed a number of substances of which some are found on the List of unwanted substances, others are carcinogenic (benzene, trichlorethylen) and in addition, some are covered by bans or limitations in use (benzene and 1,1,1-trichlorethan [8]).
However, it should be noted that this NACE-code covers many types of impregnation products and not only products for shoes or leather. In addition, the SPIN-database primarily contains information on products that are use occupationally and most shoe care products are expected to be sold solely on the retail market.
The purpose of the project is thus to map which chemical substances are used in footwear care prodcuts in the retail trade, including PBT dyes and more closely defined PFOS compounds [9] as well as to evaluate any health hazards in connection with ordinary consumers' use of the products and on this basis to establish recommendations for a safe use of the products.
Fodnoter
[1] Statbank Denmark
[3] Arbejdstilsyntes bekendtgørelse nr. 906 af 8. november 2020 om foranstaltninger til forebyggelse af kræftrisikoen ved arbejde med stoffer og materialer
[4] Miljøstyrelsens bekendtgørelse nr. 755 af 15. august 3003 om forbud mod import, salg og anvendelse af visse azofarvestoffer
[5] EPA (2004); Orientation from the EPA, No. 8, 2004: ”List of unwanted substances 2004”
[6] http://householdproducts.nlm.nih.gov
[7] NACE stands for: "Nomenclature generale des Activités economiques dans les Communautes Européennes" NACE is the designation for the common trade nomencalture in EU, i.e. the sytem EU uses to categorise all occupational trades. NACE was implemented in the EU member states in 1993.
[8] Iflg. bekendtgørelse nr. 1042 af 17. december 1997 om begrænsning af salg og anvendelse af visse farlige kemiske stoffer og produkter til specielt angivne formål, it is forbidden to sell products that contain benzene in concentrations of 0.1% or more. 1,1,1-trichlorethan is covered by bekendtgørelse nr. 243 af 19. april 2002 om visse ozonlagsnedbrydende stoffer
[9] Perfluorobutansulfonat, perfluorohexan-sulfonat, perfluorooktansulfonat, perfluorodecansulfonat, perfluorooktansulfon-amid, N-ethyl perfluorooktansulfonamid, perfluoroheptansyre and perfluorooktansyre.
Version 1.0 June 2005, © Danish Environmental Protection Agency