Most lead-based paint in the United Kingdom were banned from sale to the general public in 1992, except for specialist uses. Prior to this, lead compounds had been used as the pigment and drying agent in different types of paint, for example brick and some tile paints. Lead-based paint has been an important cause of lead poisoning.
Until the early 1960s white lead (lead carbonate/lead sulphate) was added in substantial quantities as the main white pigment in some paint products intended for use as a primer or top coat over metal and wood, both internally and externally. Examples of where this type of paint may have been used are skirting boards, doors, door frames, stairs, banisters, window frames and sills, wooden flooring, radiators, and pipes, though it could also have been applied to any other surface at this time e.g. plaster walls.
Prior to this the concentration of white lead in paint rose to its highest levels between the years 1930 and 1955, as much as half the volume in some paints, meaning many post-war UK houses have significant amounts of lead in original paint layers. [1]
In the 1950s, alternative white pigments, such as titanium dioxide, were introduced.
In 1963 a voluntary agreement was made between the then Paintmakers' Association, now the British Coatings Federation, and the UK Government that resulted in labeling of paint that contained more than 1% of lead in dry film, with a warning that it should not be applied to surfaces accessible to children. [2] However white lead-based paints remained in the supply chain and were therefore still in use for some time.
Following this, white lead continued to be added to some paint available to professional decorators for specialist use. Additionally, paint with low white lead levels was applied as a thin primer coat to some pre-fabricated domestic wooden windows until the early 1980s.
In 1992 European Union legislation [3] was implemented within the UK by the Environmental Protection, part of the Department for Environment, Food and Rural Affairs (DEFRA), as the Controls on Injurious Substances Regulations. [4] This prevented the addition of white lead to almost all paints except those intended for use in historic buildings and as artwork.
The lead-based pigments (lead tetroxide, calcium plumbate, or "red lead") were widely used as an anti-corrosive primer coating over exterior steelwork. This type of paint might have been applied to garden gates and railings, guttering and downpipes and other external iron and steelwork.
Similar red lead-based compounds were also widely used as a jointing compound in engineering, to form steam- or oil-tight flanged joints in pipework.
Red lead in paint was not banned by the 1992 legislation [4] or by more recent EU REACH regulations [5] and the SPAB confirm it is technically available in the UK but only by special licence. [6] In practice however it has been replaced by safer alternatives (such as red oxide [7] ) by most UK/EU paint suppliers; and indeed of those that still supply it, some mistakenly assume it is covered by the 1992 regulations and request approval from a 'competent body' before purchase. [8]
Until the early 1970s red, yellow, orange and green lead-based pigments (lead chromate) were added to a limited number of decorative coloured gloss and wall paints. Following this non-lead alternatives were used as pigments.
However lead chromate continued to be used in yellow road markings up to the present day. [9] Its use was supposed to cease on 21 May 2015, the sunset date set by EU REACH regulations. However a last minute request for authorization by the Canadian pigment producer Dominion Colour Corporation (DCC) has had preliminary support by the European Chemicals Agency, [10] [11] which if approved could see its use continue in road markings until 2022 or later.
Lead (lead naphthenate) was added as a drying agent to some types of paint to ensure the paint surface hardened. [1] In the 1960s this practice was phased out for ordinary paint available to the general public, however its use has not (so far) been banned by legislation.
The Lead Paint Safety Association (LiPSA) is a not-for-profit UK organisation that aims to promote awareness and best practice in lead paint safety and compliance. LiPSA's objective is to prevent and ultimately to eliminate childhood and occupational lead poisoning. LiPSA was founded by Tristan Olivier.
LiPSA's members include individuals and organisations, especially those in the area of lead paint testing and removal and offers web-based, email and telephone advice in relation to lead paint, including testing strategies. LiPSA also offers an emergency telephone support line for child lead poisoning and/or occupational exposure concerns.
Chromium is a chemical element; it has symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal.
Paint is a material or mixture that, when applied to a solid material and allowed to dry, adds a film-like layer. As art, this is used to create an image or images known as a painting. Paint can be made in many colors and types. Most paints are either oil-based or water-based, and each has distinct characteristics.
A pigment is a powder used to add color or change visual appearance. Pigments are completely or nearly insoluble and chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use. Dyes are often organic compounds whereas pigments are often inorganic. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli.
Gesso, also known as "glue gesso" or "Italian gesso", is a white paint mixture used to coat rigid surfaces such as wooden painting panels or masonite as a permanent absorbent primer substrate for painting. It consists of a binder mixed with chalk, gypsum, pigment, or any combination of these.
Cadmium pigments are a class of pigments that contain cadmium. Most of the cadmium produced worldwide has been for use in rechargeable nickel–cadmium batteries, which have been replaced by other rechargeable nickel-chemistry cell varieties such as NiMH cells, but about half of the remaining consumption of cadmium, which is approximately 2,000 tonnes annually, is used to produce colored cadmium pigments. The principal pigments are a family of yellow, orange and red cadmium sulfides and sulfoselenides, as well as compounds with other metals.
Chromate salts contain the chromate anion, CrO2−
4. Dichromate salts contain the dichromate anion, Cr
2O2−
7. They are oxyanions of chromium in the +6 oxidation state and are moderately strong oxidizing agents. In an aqueous solution, chromate and dichromate ions can be interconvertible.
Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. For several centuries the oil painting has been perhaps the most prestigious form in Western art, but oil paint has many practical uses, mainly because it is waterproof.
Anti-fouling paint is a specialized category of coatings applied as the outer (outboard) layer to the hull of a ship or boat, to slow the growth of and facilitate detachment of subaquatic organisms that attach to the hull and can affect a vessel's performance and durability. It falls into a category of commercially available underwater hull paints, also known as bottom paints.
School bus yellow is a color that was specifically formulated for use on school buses in North America in 1939. Originally officially named National School Bus Chrome, the color is now officially known in Canada and the U.S. as National School Bus Glossy Yellow.
Spray paint is paint that comes in a sealed, pressurized container and is released in an aerosol spray when a valve button is depressed. The propellant is what the container of pressurized gas is called. When the pressure holding the gas is released through the valve, the aerosol paint releases as a fine spray. Aerosol painting is one form of spray painting; it leaves a smooth, even coat, unlike many traditional rolled and brushed paints. Aerosol primer can be applied directly to bare metal and many plastics.
Lead(II,IV) oxide, also called red lead or minium, is the inorganic compound with the formula Pb3O4. A bright red or orange solid, it is used as pigment, in the manufacture of batteries, and rustproof primer paints. It is an example of a mixed valence compound, being composed of both Pb(II) and Pb(IV) in the ratio of two to one.
Chrome yellow is a bright, warm yellow pigment that has been used in art, fashion, and industry. It is the premier orange pigment for many applications.
A primer or undercoat is a preparatory coating put on materials before painting. Priming ensures better adhesion of paint to the surface, increases paint durability, and provides additional protection for the material being painted.
Lead paint or lead-based paint is paint containing lead. As pigment, lead(II) chromate, lead(II,IV) oxide,, and lead(II) carbonate are the most common forms. Lead is added to paint to accelerate drying, increase durability, maintain a fresh appearance, and resist moisture that causes corrosion. It is one of the main health and environmental hazards associated with paint. Lead paint has been generally phased out of use due to the toxic nature of lead. Alternatives such as water-based, lead-free traffic paint are readily available.
Zinc chromate, ZnCrO4, is a chemical compound, a salt containing the chromate anion, appearing as odorless yellow powder or yellow-green crystals, but, when used for coatings, pigments are often added. It is used industrially in chromate conversion coatings, having been developed by the Ford Motor Company in the 1920s.
Lead(II) chromate is an inorganic compound with the chemical formula PbCrO4. It is a bright yellow solid that is very poorly soluble in water. It occurs also as the mineral crocoite. It is used as a pigment.
Chrome orange is a mixed oxide with the chemical formula Pb2CrO5. It can be made by treating a lead(II) salt with an alkaline solution of a chromate or by treating chrome yellow (PbCrO4) with strongly basic solution.
White lead is the basic lead carbonate 2PbCO3·Pb(OH)2. It is a complex salt, containing both carbonate and hydroxide ions. White lead occurs naturally as a mineral, in which context it is known as hydrocerussite, a hydrate of cerussite. It was formerly used as an ingredient for lead paint and a cosmetic called Venetian ceruse, because of its opacity and the satiny smooth mixture it made with dryable oils. However, it tended to cause lead poisoning, and its use has been banned in most countries.
The environmental impact of paint can vary depending on the type of paint used and mitigation measures. Traditional painting materials and processes can have harmful effects on the environment, including those from the use of lead and other additives. Measures can be taken to reduce its environmental effects, including accurately estimating paint quantities so waste is minimized, and use of environmentally preferred paints, coating, painting accessories, and techniques.
Chromium toxicity refers to any poisonous toxic effect in an organism or cell that results from exposure to specific forms of chromium—especially hexavalent chromium. Hexavalent chromium and its compounds are toxic when inhaled or ingested. Trivalent chromium is a trace mineral that is essential to human nutrition. There is a hypothetical risk of genotoxicity in humans if large amounts of trivalent chromium were somehow able to enter living cells, but normal metabolism and cell function prevent this.