Kemikalier i tekstiler

Summary

Textiles sold on the Danish market contain chemicals to a varying extent. It may be a question of e.g. dyes, which provide colour to the textile, or residues/impurities from the production, e.g. aromatic amines and heavy metals, which do not have any function. This study indicates that some of these chemicals may involve a risk to the health of the consumer and the shop assistants and an environmental risk in connection with the sewage discharge from domestic laundry.

Background and purpose

Everybody is almost constantly in contact with textiles, both in the form of the clothes that we are wearing but also when for instance we sleep, we do it in sheets made from textile. It is thus very important that textiles do not contain health hazardous chemicals.

When we wash our clothes, the content of chemicals (e.g. surplus dyes) is more or less washed out and ends up in the sewerage system together with the slops. If these chemicals are not degraded in the wastewater treatment plant, they may reach the aquatic environment when discharged (e.g. a watercourse) or the farmland when sludge is applied. Chemicals hazardous to the environment may thus be spread in the environment.

Recent Swedish study

A recent Swedish study entitled "Chemicals in textiles" ([Kemikalier i tekstilier] in Swedish) treats environmentally and health hazardous chemicals in imported textiles. This study reaches the conclusion that hazardous chemicals are found within the following functional groups: Biocides, flame retardants, dyes (azo- and dispersion dyes), carriers and softeners and the substance formaldehyde etc. They are substances that serve a purpose in the final product (e.g. flame retardants and dyes) as well as residues of auxiliary chemicals from the production process (e.g. carriers and nonylphenol ethoxylates). The study only treats of health hazard to consumers and environmental hazard as the result of domestic laundry at a very comprehensive level, and the conduct regarding disposal of textiles is hardly touched on. Whether the imported textiles in Sweden correspond to the textiles on the Danish market is not known. It is, however, considered likely that the chemicals content in imported textiles on the Swedish market in general at least corresponds to the chemicals content in textiles on the Danish market. To the best of our knowledge, no studies like the one in Sweden have been made in any other country.

Delimitation

The present study comprises the Danish market, and the conditions regarding environmental and health hazards in especially the use phase and to a lesser degree in the disposal phase are discussed in detail. Clothing and furnishing textiles washed time and again are included. Only textiles of the most frequently used types of fibres are included and the clothing textiles are considered to cover 95% of this market in Denmark. Correspondingly, the types of furnishing textiles included are considered to make up approx. 40% of the market of furnishing textiles (carpets left out of account). Altogether, the types of textiles comprised by this study are considered to represent around 50% of the Danish textile market (technical textiles not included).

Purpose

The purpose of the study is to reach a number of recommendations on the basis of the use and disposal phases stating which chemicals should be avoided in the production and manufacture of textiles and indicating immediate possibilities of substitution.

The study

First, the present study includes a survey presenting which chemicals may occur in ready-to-use textiles together with a screening of their environmental and health hazards. Furthermore, textiles bought on the Danish market were analyzed for the most hazardous of the substances and so were the slops from tests with simulated domestic laundry of the textiles. The study also explains how textiles are disposed of in Denmark - including the environmental problems involved. Finally, a screening of the health hazard of the amounts of chemicals found in the textiles and an environmental risk assessment of the amounts found in the slops. This screening/risk assessment was made in order to clarify whether the chemicals found are actually of risk to health and/or the aquatic environment.

Survey

The survey, of which chemicals may (theoretically) occur in textiles in the use phase, is primarily based on the above Swedish study and on information from four large international chemicals producers regarding dyes and pigments. A description of where in the textile production chain the chemicals are used is based on existing knowledge from literature.

The hazard assessments of the chemicals surveyed are made with regard to discharge with waste water (ABC system) and health (UPH system). The mentioned systems rank (score) the substances in three groups based on their inherent hazards. In the ABC system, the substances are divided into those which are undesirable in discharges (A: Substitution recommended), those for which guiding limit values are recommended (B: Discharge limited) and, finally, those not considered harmful as long as they are not discharged in large amounts (C substances). The ABC system is described in the Guidance Document on Discharge of Industrial Waste Water to Municipal WWTPs from the Danish Environmental Protection Agency. In the same way, the UPH system divides the substances into three groups as regards health: Undesirable (U), problematic (P) and handable (H). The UPH system is based on the EU classification system for health risk (R sentences) and is developed within the framework of the so-called Four Institutes Collaboration (VKI, DTC, dk-TEKNIK and DTI). In the present study, the system was increased by an extra category (H(L): "lightly problematic") in order to separate especially the irritating and sensitizing substances from the handable substances (H). This expansion of the system is a consequence of the fact that skin contact is the most important way of exposure in the case of textiles in the use phase.

Textiles

Twenty-two textiles purchased on the Danish market were analyzed in the laboratory for the chemicals singled out at the hazard assessments as most hazardous to environment and health. The textiles are selected i.a. on the basis of criteria aimed at covering all types of fibres included in the project but also on the basis of an assessment of the immediate probability of occurrence of the prioritized chemicals.

With the purpose of examining to which degree textile chemicals are washed out during normal domestic laundering, simulated domestic laundering was performed on the purchased textile samples. Subsequently, the slops were analyzed in the laboratory for any contents of the prioritized chemicals that had been found at the analysis of the textiles.

Risk assessment/screening

In order to examine whether the textile chemicals demonstrated in the 22 textiles actually present a risk of environmental effects to the aquatic environment and/or of health effects to consumers and shop assistants, a risk screening/assessment was made. As regards environmental risk assessment of chemicals discharged with slops into the sewerage system as well as the screening of health risk to consumers and distributors (shops assistants) of chemicals demonstrated in the ready-to-use textiles, they are both based on the principles of the EU Technical Guidance Document for risk assessment.

Chemicals assessed to present an environmental and/or health risk are listed and obvious possibilities of substitution are given on the basis of existing know-how and information from chemicals producers.

Main conclusions

Consumption of textiles

The total yearly consumption (sales) of textiles in Denmark is estimated to amount to 22 kg per inhabitant of which approx. 13 kg per inhabitant are clothing textiles.

It is estimated that, in Denmark, about 50% of the amount of used clothing textiles are recycled. Furthermore, it is estimated that 10-20 kg textile per person per year are disposed of and that practically all disposal of textiles in Denmark today is made by incineration. Contributions from textiles included in the project to environmental problems associated with waste incineration, e.g. depositing of incineration residues, are considered negligible.

Among other things, the environmental risk assessment based on the results of the tests with simulated domestic laundry showed that twelve substances presented a risk of environmental effects on the aquatic environment, that effects could not be excluded as regards six other substances and that seven substances could not be assessed due to lack of data. Similarly, the screening for health risk based on the maximum concentrations found in the textiles shows that ten substances present a risk while eleven other substances present a small risk to consumers and/or shop assistants. Due to lack of data, the screening for health risk could not assess nineteen substances.

It can be concluded that this study, which must be charaterized as limited compared to the large and varied textile market, indicates that the following substances should be avoided (or limited) in textiles as they are considered to present greater or less health and/or environmental risk:

• Nicotine
• Naphthalene
• o-Chlorophenol
• Diethylhexyl phthalate (DEHP)
• Nonylphenol ethoxylates (NPEO)
• C₃-alkylbenzenes
• C₄-alkylbenzenes
• Tetrachloroethylene
• p-Chloroanililne
• p-Nitroaniline
• 2,6-dichloro-4-nitroaniline
• 2-chloro-4-nitroaniline
• 6-methyl-3-nitroaniline
• Diphenylamine
• Toluene diisocyanate
• Acridine
• Nitrobenzene
• Highly soluble barium compounds
• Cadmium
• Cobalt
• Chromium
• Lead
• Arsenic
• Mercury
• Tin
• Zinc
• Nickel

In the table below, each substance is examined with regard to environmental and/or health risk.

Possibilities of substition

These twenty-seven substances are dominated by impurities in dyes (anilines, acridine, nitrobenzene, diphenylamine and heavy metals) and partly by carriers (C₃- and C₄- alkylbenzenes, tetrachloroethylene and naphthalene). As to heavy metals, it is recommended to avoid if possible the use of heavy metal-based dyes/pigments and to minimize the content of heavy metal impurities in dyes/pigments. A reduction of the content of aryl amine and other impurities in the form of acridine, nitrobenzene and diphenylamine is also recommended. Furthermore, it is recommended that the presence of cadmium and DEHP in PVC prints is eliminated or alternatively to avoid PVC prints. To a great extent, the use of carriers may be avoided by using high-temperature dying except when dying mixed textiles containing wool. In this case, carriers with least impact on health and the environment should be applied. Among the carriers demonstrated in the analyzed textiles, diethylphthalate is immediately assessed to belong with the carriers with relatively little impact on health and the environment. I.a., alcohol ethoxylates are considered a possible substitute for nonylphenol ethoxylates. It has not been possible to throw light on the precise use of nicotine and no substitutes can thus be suggested. As regards polyurethane products, the presence of tin (especially the out-washable part) and toluene diisocyanate should be avoided. The presence of toluene diisocyanate may be limited by optimum polymerization (hardening) of the polyurethane.

As regards the development requirements, special mention may be made of the following topics: Clarification of the environmental importance of washing out of dyes by domestic laundry, clarification of the possibilities of minimizing impurities in dyes/pigments, how much does repeated domestic laundering influence the content of chemicals in the textile and where and with which purpose is nicotine used.

Project results

Hazard screening

Hazard screening was made of 190 chemicals potentially occurring in textiles. Fifty-five substances ended up in the most hazardous category (A) and 52 substances in the least hazardous group (C) as far as hazard to the aquatic environment is concerned. Sixty-eight substances could not be assessed due to lack of data. In similar hazard screenings regarding health, 8 substances ended up in the most hazardous category (U) and 77 substances in the least hazardous group (H). In this case, 18 substances could not be assessed because of lack of data. As regards the aquatic environment, the most hazardous chemicals were found among the carriers, anticrease agents and biocides while the most hazardous chemicals with regard to health were found among carriers, biocides, optical brighteners and fixing agents. Only four substances/groups of substances were assigned to the most hazardous category regarding aquatic environment as well as health. They were: Dimethyl formamide, chlorinated ethylenes, potassium dichromate and pentachlorophenol.

Chemical analyses

Twenty-two textile products (trousers, sheets, underwear, etc.) were purchased and analyzed in the laboratory for the chemicals singled out at the hazard assessments as most hazardous. It was estimated that the types of purchased textile products represent approx. 10% of the annual sale in Denmark. Among other things, the chemical analyses demonstrated the presence of naphthalene, o-chlorophenol, nicotine, various phthalates, quaternary ammonium compounds, nonylphenol ethoxylates, chlorinated benzenes, alkylbenzenes, 14 aryl amines, substituted toluenes, benzene sulfonamides, polycyclic compounds, substituted benzenes and the following heavy metals: Lead, cadmium, copper, cobalt, chromium, nickel, zinc, barium, tin, arsenic and mercury.

Simulated domestic laundry was made on all of the purchased textile products and the slops were analyzed for the chemicals found in the textiles. In the slops, the following chemical substances and heavy metals were found: Naphthalene, nicotine, nonylphenol ethoxylates, tetrachloroethylene, trimethyl benzene, biphenyl, 9 aryl amines, substituted toluenes, benzene sulfonamides, acridine, isoquinoline and the metals: Cobalt, chromium, copper, nickel, cadmium, lead, tin, zinc and barium. The percentages of chemical washed out range from less than 1‰ to more than 100%. The latter is probably the result of the fact that certain substances (e.g. short-chained nonylphenol ethoxylates) may be produced during the laundering process. Among the substances least washed out were chlorinated carriers and substituted toluenes while the washing out of i.a. some phthalates, some heavy metals and benzene sulfonamides is rather high.

Ecolabelling schemes

By comparing the chemicals found, including the concentrations in the textiles, with the criteria in the two ecolabelling schemes "the Swan" and "the Flower" and in Öko-tex, none of the examined textile products seems on the basis of an immediate evaluation to live up to all the requirements of the schemes.

Risk assessment/screening

The table below shows the substances singled out by the environmental risk assessment and the screening for health risk made.

Chemicals in textiles singled out by risk assessment/screening

Environmental risk assessment was made of all the substances found in the slops and of dyes/pigments including some aryl amines. In relation to domestic laundry of textiles similar to those examined in this study, some substances are likely to present a risk of environmental effects on the aquatic environment and/or on the terrestrial environment in relation to application of sewage sludge on farmland. These substances are considered to include: Nicotine, diethylhexyl phthalate (DEHP), nonylphenol ethoxylates (NPEO), 2,6-dichloro-4-nitroaniline, 2-chloro-4-nitroaniline, 6-methyl-3-nitroaniline, diphenyl amine, acridine, cadmium, chromium, lead and zinc.

Other substances are less likely to present environmental hazards but it cannot be excluded on the present basis. They comprise: 4-Methyl-3-nitroaniline, p-chloroaniline, N-butylbenzene sulfonamide, cobalt, tin and copper.

Dyes

Add to this washed-out dyes, which with respect to azo-compounds undergo reductive cleavage into aryl amines under reductive conditions (e.g. in wastewater treatment plants) and are thus likely to contribute considerably to the environmental impact with aryl amines. Furthermore, it should be noted that although the performed risk assessment of the individual aryl amine does not present a risk of environmental effects, the aryl amine will contribute to the total amount of aryl amines present in a domestic laundry. As the effect potential of aryl amines is clearly additive, situations are likely to occur in which the total amount of aryl amines presents a risk although the individual aryl amines do not. This should be seen in light of the fact that this study demonstrates that the presence of aryl amines (and azo-dyes) in textiles is widespread.

Substances that were demonstrated in the slops but of which the risk could not be assessed due to lack of data include: 2-Bromo-6-chloro-4-nitroaniline, 2-cyano-4-nitroaniline, 6-bromo-2,4-dinitroaniline, 6-chloro-2,4-dinitroaniline, methyl diphenylamines, N-ethyl toluene sulfonamide and N-methyl toluene sulfonamide. To this must be added dyes that are visually demonstrated in the slops.

Washing out

The risk assessment performed in this study is solely based on data from first laundering of textiles. The washing out of the demonstrated textile chemicals varied from less than 1‰ to 100%. For most of the substances, far under half of the amount present was washed out, e.g., the washing out was less than 10% for more than 80% of the aryl amines demonstrated. Therefore, it is not unlikely that, with respect to several of the substances, a considerable washing out will occur in the following launderings.

Health risk screening

The health risk screening of the substances found in the textiles shows that the following substances must be considered problematic as the concentrations found present a risk of health effects on the users of the textiles and/or the shop assistants (see table above): Nicotine, naphthalene, o-chlorophenol, C₃-alkylbenzenes, C₄-alkylbenzenes, tetrachloroethylene, p-chloroaniline, p-nitroaniline, toluene diisocyanate and nitrobenzene. To these must be added the following substances that, similarly, are considered to present a small risk: DEHP, acridine, readily soluble barium compounds, cadmium, cobalt, chromium, lead, arsenic, mercury, nickel and tin.

It cannot be excluded that also other substances demonstrated in the textiles may be of risk to health as a health risk screening of these substances has not been possible due to lack of adequate toxicological data. They are: 2-Bromo-6-chloro-4-nitroaniline, 3,5-dinitrobromobenzene, 2-chloro-4-nitroaniline, 2-cyano-4-nitroaniline, 6-bromo-2,4-dinitroaniline, 6-chloro-2,4-dinitroaniline, N-ethyltoluene sulfonamide, n-butylbenzene sulfonamide, N-methyl toluene sulfonamide, 6-methyl-3-nitroaniline, 4-methyl-3-nitroaniline, 4-chloro-2-nitronailine, isoquinoline, indan, methyldiphenylamine, (1-chloro-dodecyl) benzene, (1-chloro-1-methylundecyl) benzene, methylindan and 2-methyl naphthalene.

Some textiles contain a lot of different substances, which, in combination, may be of risk to health especially as many of the substances (e.g. aniline derivatives) are most likely to have the same effect. It has, however, not been possible to quantify the risk on the basis of the present data.

More literature

"Chemicals in textiles - report on a government assignment" [Kemikalier i textilier - redovisning av et regeringsuppdrag]. KEMI 2/97. Kemikalieinspektionen, Solna, Sweden. February 1997, in Swedish.