Introduction: types of potentially toxic building materials

The construction industry is one of the largest and most active sectors in the world and in the next decades will keep on growing at a very fast pace. For instance, China will need 40 billion square meters of combined residential and commercial floor space over the next 20 years – equivalent to adding one New York every two years (Pacheco-Torgal and Jalali, 2011). Buildings have high energy consumption and account for a significant part of carbon dioxide emissions. Since 1930 more than 100,000 new chemical compounds have been developed, and insufficient information exists for health assessments of 95% of chemicals that are used to a significant extent in construction products (Pacheco-Torgal and Jalali, Pacheco-Torgal and Jalali, 2011). Moreover, many buildings currently suffer from problems related to excessive moisture with mold formation, or present low humidity levels, giving rise to respiratory diseases. A recent investigation (Fisk et al., 2011) shows that improving indoor environmental quality in the stock of US office buildings would generate a potential annual economic benefit of approximately $20 billion. So it is rather obvious that the indoor air quality must be put in the center of eco-efficient building design.

Many books have been written about building materials, covering their physical and mechanical properties and more recently their durability. But the focus has now shifted to their environmental performance, in order to answer the question of how building materials can contribute to the ecoefficiency of the construction industry. Reducing the toxicity of building materials is part of the ‘greening’ process, and avoiding the use of materials that release pollutants is one of the principles of eco-efficient construction. Indoor pollutants include volatile organic compounds (VOC), formaldehyde, semi-volatile organic compounds (SVOC), radon, NOx, asbestos and nanoparticles. Homes contain a large amount of chemicals and heavy metals that either contaminate indoor air or pollute tap water, thus causing several health-related problems such as asthma, itchiness, burning eyes, skin irritations or rashes, nose and throat irritation, nausea, headaches, dizziness, fatigue, reproductive impairment, disruption of the endocrine system, cancer, impaired child development and birth defects, and immune system suppression. However, and contrary to general belief, buildings usually contain many toxic materials, some of which even comply with legal regulations. For instance, the threshold for lead in drinking water was reduced from 300 μg/l in the 1970s to 50 μg/l in the 1980s and 25 μg/l in the 1990s and will be reduced again to just 10 μg/l from 25 December 2013. The reason for that long delay has much to do with the fact that the replacement of lead pipes just in Europe would cost around 200,000 million euros. Recent recommendations towards the reduction of indoor air exchange rate to minimize energy consumption contribute to increasing the effects of hazardous substances on human health. Ironically, this means that the economic savings in energy bills will be offset by much more expensive medical bills.

On 9 March 2011 the European Union approved Regulation (EU) 305/2011, the Construction Products Regulation (CPR), that replaced Directive 89/106/EEC, already amended by Directive 1993/68/EEC, known as the Construction Products Directive (CPD). The new CPR was published in the Official Journal of the European Union (OJEU) on 4 April 2011. In accordance with Article 68, the CPR entered into force on 24 April, the 20th day following its publication in the OJEU. This includes Articles 1 and 2, 29 to 35, 39 to 55, 64, 67 and 68, and Annex IV. However, Articles 3 to 28, 36 to 38, 56 to 63, 65 and 66, as well as Annexes I, II, III and V, shall apply from 1 July 2013. This means that only by 1 July 2013 will the CPR will be fully enforced without the requirement for any national legislation. Being a Regulation means that it ‘shall have general application. It shall be binding in its entirety and directly applicable in all Member States’ while the CPD was ‘binding, as to the result to be achieved, upon each Member State to which it is addressed, but shall leave to the national authorities the choice of form and methods’. This also means that the UK, Ireland and Sweden will then lose their ‘opt-out’ clause employed under the CPD period.

When comparing the basic requirements of the CPR and CPD, one can see that the CPR has a new requirement, no. 7 (Sustainable use of natural resources), and also that no. 3 (Hygiene, health and the environment) and no. 4 (Safety and accessibility in use) have been refined. This means that a new and more environmentally friendly approach will determine the manufacture of construction products. A crucial aspect of the new regulation relates to the information regarding hazardous substances. While the CPD considered only a very limited range of dangerous substances, e.g. formaldehyde and pentachlorophenol, the CPR links this subject to Regulation (EC) No. 1907/2006 (Registration, Evaluation, Authorisation and Restriction of Chemicals – REACH Regulation). The introduction of the CPR states that ‘the specific need for information on the content of hazardous substances in construction products should be further investigated’. Besides, Article 67 mentions that ‘By 25 April 2014, the Commission shall assess the specific need for information on the content of hazardous substances in construction products and consider the possible extension of the information obligation provided for in Article 6(5) to other substances’.

Toxicity aspects have been a field outside the boundaries of the construction industry, with its practitioners belonging to the realm of health professionals. That is why architects, civil engineers and other professionals involved in the construction industry have so little knowledge about this area. This means that a new approach to building materials is needed that is capable of solving this complex problem – a more integrative approach that is capable of joining the best efforts of construction practitioners and health specialists. Bringing together important contributions from several international experts from very different specialties, this book is intended to fill the aforementioned gap by analyzing several aspects related to the toxicity of building materials.