29 June 2021


We expect the buildings we work, live and socialise in to be safe and free from materials that would be harmful to us and the world around us.

For the past almost two decades, the International Living Future Institute (ILFI) has been working towards this goal with the development of the Living Building Challenge (LBC) Red List.

What is the Red List

Developed by the ILFI, in collaboration with the Healthy Building Network and the Pharos Project in 2006, the LBC Red List represents the materials, chemicals and elements used in the building products industry, that are known to be a risk to human and environmental health.

The ILFI believe the following materials should be phased out of production, with the Red List continuously being added to as each new version of the LBC Standard is released:

Alkylphenols
These are organic compounds used in a wide variety of building products, such as inclusion in surfactants, PVC intermediates, and as an epoxy resin hardener. The actual danger comes from this compound being highly soluble and ends up being washed into our waterways.
Asbestos
This is a naturally occurring mineral made up of soft, flexible, and heat-resistant fibers. As such, asbestos is a highly effective insulator, although when absorbed into the body, this mineral tends to stay inside permanently causing damage over time. It is commonly found in flooring, ceiling, and roofing tiles, as a cement additive, in adhesives, insulation, and in fireproofing materials.
Bisphenol A (BPA)
This is an organic synthetic compound typically used as a precursor to important plastics because of its resistance to solubility in water. It is typically used in making plastics that are clear, tough, and flame resistant. In building materials it is found in high performance coatings such as paints, floor sealers, protective coatings, adhesives, fillers, fiberglass binders, and as a cement additive.
Cadmium
Cadmium is typically a byproduct of mining, although it is also produced in the smelting and refining of zinc. It is highly toxic, affecting the kidneys and the bones, and is also an inhaled carcinogen. As a building material it could be found in the production of paints and of tinting materials. It is used in metal manufacturing and finishes such as galvanizing and electroplating. It is also used as a PVC stabilizer, mainly in the production of door and window frames, water and drainpipes and hoses, and in insulation purposes.
Chlorinated polyethylene
This material is created by chlorinating high-density polyethylene, resulting in a durable thermoplastic. It is easy to shape and highly resistant to ageing caused by exposure to heat. It is also durable against typical weathering and against impacts, which is why it is mixed in with other compounds. It could be found in building materials used for below ground drainage, doors, windows, and in any material that is insulated against rainwater.
Chlorosulfonated polyethlene (CSPE)
This material is a synthetic rubber, and is typically known as Hypalon, a trade name from its developer DuPont. It is used in construction because of its high resistant to weathering, UV stability, and good adhesion properties. These qualities make it immensely ideal for roofing purposes. It is also used as wire and cable sheathing and insulation, and included in paint as well. While also resistant to heat, once it starts burning, it releases toxic emissions such as carbon monoxide, sulfur dioxide, hydrogen chloride, and other harmful byproducts.
Chlorofluorocarbons
This organic compound, while not directly toxic or harmful to living beings, does have the tendency to accumulate in the stratosphere and contribute to the depletion of the ozone layer. Relevant to construction and building materials, this compound is typically used as a cooling and refrigerant, found in refrigerators and in air conditioning units. They are also commonly found in sprays and aerosol cans. The concern from these items is when they leak or contaminate into the atmosphere or into the ground. 
Chlorobenzene
This is an aromatic organic compound, easily identifiable by its almond-like odour. There have been numerous documented cases of this compound as being highly dangerous for people with a disposition toward pulmonary conditions. Relevant to building materials, it is typically found in adhesives, binding agents, and as an additive used to promote hardening. It is also found in numerous paints and plastics.
Chloroprene
This organic compound is used to create the first oil resistant synthetic rubbers. It is also typically used as raw material for manufacturing both water-based and solvent adhesives, as well as for molded foam, sound insulation, gaskets, and multi-purpose rubber sheathing. This compound, however, is deemed highly dangerous to humans, as exposure could potentially lead to cancer, reproductive system damage, eye and skin irritation, hair loss, and even damage to the kidneys, liver, and lungs.
Chromium VI
Hexavalent chromium is the element chromium present in any chemical compound that is in the +6 oxidation state. Chronic exposure to a compound with this element could increase the risk of developing respiratory cancer, cancer in the oral cavity, and in the small intestine. It is so toxic that the liver is not able to detoxify it once it enters the human body. It is largely found in paints, inks, plastics, and pigments. It could also be given off during casting, cutting and welding operations of metals used in construction.
Chlorinated Polyvinyl Chloride (CPVC)
This thermoplastic is produced by the chlorination of polyvinyl chloride resin, making it far more flexible and able to resist higher temperature variations. As a building material, it is typically used in hot and cold water delivery pipes, and also in industrial liquid handling and distribution. While this material in itself has been deemed as safe for the transport and distribution of drinking water, it still is PVC-based, and every part of the PVC lifecycle involves the release of highly toxic chlorine-based chemicals. These chemicals are associated with various health issues, such as cancer, immune system damage, and even hormone disruption.
Formaldehyde (added)
This strong-smelling gas is often found as a liquid solution and is used as a chemical preservative in medical purposes, although it is also found in many household products, glues, and paper product coatings. In construction settings, it is found in particle board, fiberboard, and plywood. This chemical is so potent that it immediately causes an immune system response upon initial exposure. Further exposure could cause damage to the eyes, nose and throat, triggering fits of coughing and wheezing.
Halogenated flame retardants (HFRs)
The irony of this compound is that it is primarily intended for safe use in ensuring lives are protected from fires. The combination the chemicals in halogenated flame retardants, however, are being associated with the development of health issues in both humans and animals, leading to cancer, immunotoxicity, thyroid and endocrine disruption, reproductive toxicity, and even adverse neurological effects on children as they develop should they be exposed. In many cases these harmful compounds are still used as building insulation to this day.
Hydrochlorofluorocarbons (HCFCs)
Much like Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) can be found in refrigeration and air conditioning applications, and just like CFCs, they are immensely resistant to degradation, meaning they tend to stay around for a very long time. This lingering effect has been noted to be quite hazardous to the environment, particularly the ozone layer. As part of the listed ozone-depleting substances, HCFC is also seen as a Greenhouse effect contributor, and there are moves being done to replace their use with alternative freons for now.
Lead (added)
As a building material, lead is used extensively for its properties. This includes its high density, making it quite resilient, its ductility, which allows it to be shaped into various forms, its resistance to oxidation, making it immune to rust, and its general abundance, making it relatively inexpensive to use. As such, lead could be found in cable and wire casings, in cast iron pipes and gaskets, in stained glass linings, in paint and surface coatings, and even in structural steel primers. Lead, however, is highly toxic, and when exposed, could lead to abdominal pains, constipation, headaches, memory loss, and general weakness.
Mercury
There is a running debate as to how much Mercury one needs to be exposed to for it to be considered toxic. Nevertheless, even low exposures can have ill effects on people, including insomnia, memory loss, headaches, and even cognitive and motor dysfunction. Greater exposure has been observed to lead to death from kidney failure. As a building material, Mercury could be found in silent switches, thermostats and manometers, fluorescent and HID light bulbs, and in batteries for smoke detectors and emergency lighting.
Polychlorinated Biphenyls (PCBs)
This compound is an organic chemical and has been used as a building material as far back as the 1930s. Typically found in closed system electrical applications, it has also been used as caulking in buildings, and it is a certainty that older building still standing today have it. PCBs are hazardous because they are largely listed as a carcinogen and are believed to cause cancer in people.
Perfluorinated Compounds (PFCs)
This group of chemicals is primarily used as surface protection agents that really last. Its longevity is what makes this chemical group quite hazardous. If absorbed by the body, it has a half-life of more than four years. This compound is believed to be a carcinogen, causing testicular, mammary gland, pancreatic, and liver tumors. PFCs are typically found today as stain protectors on carpets and other surfaces, as well as in food wrappers and Teflon-coated items.
Phthalates
This chemical compound is primarily used to make PVC items used as building materials more flexible, pliant, and durable. In cases where specific shapes are needed for PVC application, this compound makes it possible. This compound is also used to make flooring surfaces and wall covering more durable and easier to clean. The danger comes from repeated exposure to it, particularly in pregnant women. There are cases wherein exposed pregnant mothers had children that developed behavioral and learning issues, as well as reproductive tract defects.
Polyvinyl Chloride (PVC)
PVC is among the most widely used building materials in the market, being used in window and door profiles, pipes and fittings, roofing and flooring applications, wall coverings, internal and external cladding, and even in power and telecom wiring and cables. The problem lies in the fact that PVC contains a host of dangerous chemicals and substances, most of which are dangerous on their own, and when put together becomes a potential toxic cocktail of ingredients.
Polyvinylidene Chloride (PVDC)
Similar in composition and properties to PVC, PVDC also provides superior protection against water and moisture. It is so effective as a coating that it can even protect against oxygen, which is why it is used on screens, artificial turf, and underground applications where moisture could be prevalent. Since it is similar to PVC, the same concern applies to it as it contains chlorine, which is highly toxic.
Short Chain Chlorinated Paraffins
This compound contains numerous chemicals and substances, which when put together creates a compound primarily used as a component of lubricants, and coolants for metal cutting and forming applications. As a building material it is added to paint and other coatings because of flame retarding properties. It is also found in several adhesives and sealants as an ingredient. This compound is a known skin and eye irritant and is also listed as a possible carcinogen.
Wood treatments containing creosote, arsenic or pentachlorophenol

Wood, being the only other building material that is an alternative to concrete, needs certain treatments to make it more durable and suitable to be used as such. One such treatment is with creosote, a compound that preserves wood and prevents rotting. Unfortunately, it is also a lung irritant when inhaled, and direct exposure could cause skin blistering, peeling, and reddening.

Arsenic is another substance used to treat wood for use as a building material. Immensely toxic, it is used to treat the wood to deter wood-eating insects, although the toxicity does not limit itself only to insects, as it also affects humans as well.

Pentachlorophenol is a compound used in wood preservation as it also deters wood-eating insects from degrading the wood. It also happens to be highly toxic, and even short-term exposure through inhalation is dangerous. This compound affects the kidney, blood, liver, immune system, and the respiratory tract. It is even being eyed as a possible carcinogen.

Volatile Organic Compounds (VOCs) in wet applied products
Almost every indoor area has one form of volatile organic compound (VOC) or another, as they are used as both paint additives and paint strippers, adhesives, caulks and sealants, varnish and finishing applications, and in flooring and carpets. VOCs are also a primary ingredient in many indoor cleaning products and air fresheners. As many uses as VOCs have in around homes and buildings, they also have just as many ill health effects. Exposure to VOCs is believed to cause conjunctival irritation, headaches, dyspnea, nausea, fatigue, epistaxis, dizziness, emesis, nose and throat irritation, and varying degrees of skin irritation.

Exceptions to the Red List

There are, however, specific exceptions to some of the items in this list, as they could be found in minute traces in complex products, mostly those that have compounds of several chemicals mixed in.

Declaring Red List items

As the chemicals and compounds in the Red List are of varying levels of toxicity, there have been material evaluation programs created to ensure building materials containing any of the items on this list are properly identified.

This includes declaration, which requires a manufacturer to disclose all of their product's constituent chemicals and materials, including the amount present (to the designated 100 parts per million of PPM). The manufacturer is required to report the extent that their product is compliant with the Red List. Compliance to the Red List typically comes in three levels:

  1. Free: The product is completely devoid of any of the items that appear in the Red List
  2. Compliant: The product may contain some chemicals that has been designated as temporary Red List exceptions for one reason or another
  3. Declared: Products in this level are not compliant at all with the Red List or any specified temporary exceptions

At NBS, we request all manufacturers listing their products on NBS Source to declare any Red List items, so specifiers can be confident that they have all the information they need to make informed decisions when specifying products and systems.

NBS Source integrates directly with our specification writing software, NBS Chorus, making it easy for specifiers to find, select and specify manufacturer products at the click of a button.

Find out more about NBS Source here.