Editing Compact fluorescent lamp (section)

== Health and environmental impact ==
{{Main|Fluorescent lamps and health}}
[[File:Closed double envelope compact fluorescent lamp.jpg|thumb|right|Closed double-envelope CFL]]

=== General ===
According to the European Commission [[Scientific Committee on Emerging and Newly Identified Health Risks]] (SCENIHR) in 2008, CFLs may pose an added health risk due to the [[ultraviolet]] and blue light emitted. This radiation could aggravate symptoms in people who already suffer skin conditions that make them exceptionally sensitive to light. The light emitted by some single-envelope CFLs at distances of less than {{convert|20|cm|abbr=on}} could lead to ultraviolet exposures approaching the current workplace limit set to protect workers from skin and retinal damage. However, industry sources claim the UV radiation received from CFLs is too small to contribute to skin cancer and the use of double-envelope CFLs "largely or entirely" mitigates any other risks.<ref name="GreenFacts">{{cite web |title=Energy-Saving Lamps & Health |publisher=GreenFacts site |access-date=2009-06-10 |url=http://copublications.greenfacts.org/en/energy-saving-lamps/}}</ref>

Tests have shown that radiation exposure from CFLs is negligible at 150 centimeter distance from the source. At closer distances, comparisons show that CFLs emit less UVA (long wavelength) radiation than incandescent light bulbs. They do, however, emit higher levels of UVB (short wavelength) radiation.<ref name="PubMed">{{cite journal|title=Ultraviolet light output of compact fluorescent lamps: comparison to conventional incandescent and halogen residential lighting sources |pmid=19395458 |doi=10.1177/0961203309103052 |volume=18 |issue=6 |journal=Lupus |pages=556–60 |last1=Nuzum-Keim |first1=AD |last2=Sontheimer |first2=RD |year=2009 |s2cid=206597819}}</ref> UVB can penetrate deep into the skin while sufficient levels of UVA can burn superficial layers. Closed (double-envelope) CFLs are shielded and emit a lower total UV radiation compared to incandescent or halogen bulbs of a similar wattage.

For the average user, UV radiation from indoor lights does not appear to be a concern. For those with skin sensitivity long term indoor exposure may be a concern, in which case they may want to use a bulb with lower UV radiation output. There seems to be more variability within bulb types than between them, but the best option is shielded CFLs.

A 2012 study comparing cellular health effects of CFL light and incandescent light found statistically significant cell damage in cultures exposed to CFL light. Spectroscopic analysis confirmed the presence of significant UVA and UVC radiation, which the study's authors conjectured was attributable to damage in the bulbs' internal phosphor coatings. No cellular damage was observed following exposure to incandescent light of equivalent intensity. The study's authors suggest that the ultraviolet exposure could be limited by the use of "double-walled" bulbs manufactured with an additional glass covering surrounding the phosphor-coated layer.<ref>{{cite journal |last1=Mironava |first1=T. |last2=Hadjiargyrou |first2=M. |last3=Simon |first3=M. |last4=Rafailovich |first4=M. H. |date=20 Jul 2012 |title=The Effects of UV Emission from Compact Fluorescent Light Exposure on Human Dermal Fibroblasts and Keratinocytes In Vitro |journal=Photochemistry and Photobiology |doi=10.1111/j.1751-1097.2012.01192.x |pmid=22724459 |volume=88 |issue=6 |pages=1497–1506|s2cid=2626216}}</ref>

When the base of the bulb is not made to be flame-retardant, as required in the voluntary standard for CFLs, overheating of the electrical components in the bulb may create a fire hazard.<ref>[http://www.cpsc.gov/CPSCPUB/PREREL/prhtml05/05005.html CPSC, Teng Fei Trading Inc. Announce Recall of Energy Saving Light Bulbs] {{webarchive |url=https://web.archive.org/web/20130108185759/http://www.cpsc.gov/CPSCPUB/PREREL/prhtml05/05005.html |date=January 8, 2013}}. U.S. Consumer Product Safety Commission press release. Accessed 1 January 2008.</ref>

=== Mercury content ===
[[File:Mercury emissions by light source EPA 2008.svg|thumb|upright|Net mercury emissions for CFL and incandescent lamps, based on EPA FAQ sheet, assuming average U.S. emission of 0.012 mg of mercury per kilowatt-hour and 14% of CFL mercury contents escapes to environment after land fill disposal]]
CFLs, like all [[fluorescent lamp]]s, contain [[Mercury (element)|mercury]]<ref>{{cite web |url=http://www.informinc.org/fact_P3NJlampcontract.php |title=Mercury Content Information Available for Lamps on the 2003 New Jersey Contract T-0192 |access-date=2007-05-15 |archive-url=https://web.archive.org/web/20051230010537/http://www.informinc.org/fact_P3NJlampcontract.php |archive-date=2005-12-30}}</ref><ref>{{cite web|url=http://www.ccme.ca/assets/pdf/merc_lamp_standard_e.pdf |title=Canada-Wide Standard for Mercury-Containing Lamps |access-date=2007-03-23 |date=2001 |url-status=dead |archive-url=https://web.archive.org/web/20060812071611/http://www.ccme.ca/assets/pdf/merc_lamp_standard_e.pdf |archive-date=August 12, 2006}}</ref> as vapor inside the glass tubing. Most CFLs contain 3–5&nbsp;mg per bulb, with the bulbs labeled "eco-friendly" containing as little as 1&nbsp;mg.<ref>{{cite web |url=http://www.energystar.gov/ia/partners/promotions/change_light/downloads/Fact_Sheet_Mercury.pdf |title=Frequently Asked Questions Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury June 2008 |access-date=2008-08-31 |date=2008}}</ref><ref>{{cite web |title=Mercury in Fluorescent Lamps |url=http://www.efi.org/factoids/mercury.html |publisher=Energy Federation Incorporated |work=FAQ |access-date=2009-07-02 |url-status=dead |archive-url=https://web.archive.org/web/20090810203903/http://www.efi.org/factoids/mercury.html |archive-date=2009-08-10}}</ref> Because [[Mercury poisoning|mercury is poisonous]], even these small amounts are a concern for [[landfill]]s and waste [[incinerator]]s where the mercury from lamps may be released and contribute to air and water [[pollution]]. In the U.S., lighting manufacturer members of the [[National Electrical Manufacturers Association]] (NEMA) have voluntarily capped the amount of mercury used in CFLs.<ref name=NEMAHgCap>{{cite web |url=http://www.nema.org/media/pr/20070313a.cfm |title=NEMA Lamp Companies Announce Commitment to Cap CFL Mercury Content |access-date=2007-03-23 |url-status=dead |archive-url=https://web.archive.org/web/20070715223143/http://nema.org/media/pr/20070313a.cfm |archive-date=July 15, 2007}}</ref> In the EU the same cap is required by the [[RoHS]] law.

In areas where electric power is mostly generated in coal-fired stations, replacing incandescent bulbs by CFLs actually reduces mercury emissions. This is because the reduced electric power demand, reducing in turn the amount of mercury released by coal as it is burned, more than offsets the amount of mercury released from broken and discarded CFL bulbs.<ref>{{cite web |url=http://www.energystar.gov/ia/partners/promotions/change_light/downloads/Fact_Sheet_Mercury.pdf|title=Frequently Asked Questions, Information on Proper Disposal of Compact Fluorescent Light Bulbs (CFLs)|access-date=2007-03-19}}</ref> In July 2008 the U.S. EPA published a data sheet stating that the net system emission of mercury for CFL lighting was lower than for incandescent lighting of comparable lumen output. This was based on the average rate of mercury emission for U.S. electricity production and average estimated escape of mercury from a CFL put into a landfill.<ref>{{cite web|url=http://www.energystar.gov/ia/partners/promotions/change_light/downloads/Fact_Sheet_Mercury.pdf |title=''Frequently Asked Questions Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury July 2008'', accessed 2009 Dec 22 |access-date=2012-07-15}}</ref> Coal-fired plants also emit other heavy metals, sulfur, and carbon dioxide.

In the United States, the U.S. Environmental Protection Agency estimated that if all 270&nbsp;million CFLs sold in 2007 were sent to landfill sites, around 0.13 metric tons of mercury would be released, 0.1% of all U.S. emissions of mercury (around 104 metric tons that year).<ref name="hgsheet">{{cite web|website=energystar.gov|url=https://www.energystar.gov/ia/partners/promotions/change_light/downloads/fact_sheet_mercury.pdf|title=Frequently Asked Questions: Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury|quote=What are the mercury emissions caused by humans? Do CFLS that wind up in a landfill contribute to these emissions?|date=November 2010|access-date=2017-03-23}}</ref>
The graph assumes that CFLs last an average of 8,000 hours regardless of manufacturer and premature breakage. In areas where coal is not used to produce energy, the emissions would be less for both types of bulb.<ref name="hgsheet" /><!-- Surprise: same thing -->

Special handling instructions for breakage are not printed on the packaging of household CFL bulbs in many countries. The amount of mercury released by one bulb can temporarily exceed U.S. federal guidelines for chronic exposure.<ref>{{ cite news |url=https://www.boston.com/news/local/articles/2008/02/26/mercury_leaks_found_as_new_bulbs_break/?page=1 |title=Mercury leaks found as new bulbs break |work=The Boston Globe |last=Daley |first=Beth |date=February 26, 2008 |access-date=2009-03-07}}</ref><ref name="maine.gov">{{cite web |url=http://maine.gov/dep/rwm/homeowner/cflreport.htm |title=Maine Compact Fluorescent Lamp Breakage Study Report |date=February 2008 |access-date=2009-03-07 |publisher=State of Maine, Dept of Environmental Protection}}</ref> ''Chronic'', however, implies exposure for a significant time, and it remains unclear what the health risks are from short-term exposure to low levels of elemental mercury.<ref name="maine.gov" /> Despite following EPA best-practice clean-up guidelines on broken CFLs, researchers were unable to remove mercury from carpet, and agitation of the carpet&nbsp;— such as by young children playing&nbsp;— created localized concentrations as high as 0.025&nbsp;mg/m<sup>3</sup> in air close to the carpet, even weeks after the initial breakage.<ref name="maine.gov" />

The [[U.S. Environmental Protection Agency]] (EPA) has published best practices for cleanup of broken CFLs, and ways to avoid breakage, on its web site.<ref>{{cite web |url=http://www2.epa.gov/cfl/cleaning-broken-cfl |title=Cleaning Up a Broken CFL |date=6 June 2013 |access-date=18 June 2013 |publisher=[[United States Environmental Protection Agency]] |archive-date=7 December 2021 |archive-url=https://web.archive.org/web/20211207223532/https://www.epa.gov/cfl/cleaning-broken-cfl |url-status=dead }}</ref> It recommends airing out the room and carefully disposing of broken pieces in a jar. A Maine Department of Environmental Protection (DEP) study of 2008 comparing clean-up methods warns that using plastic bags to store broken CFL bulbs is dangerous, because vapors well above safe levels continue to leak from the bags. The EPA and the Maine DEP recommend a sealed glass jar as the best repository for a broken bulb.<ref>{{cite web |url=http://www.maine.gov/dep/rwm/homeowner/cflreport.htm |title= Maine Compact Fluorescent Light Breakage Study Report |date=February 2008 |access-date=2011-07-18 |publisher= Maine Department of Environmental Protection}}</ref>

Since the end of 2018, the export, import and manufacture of CFLs within the European Union has been prohibited under the EU Mercury Regulation.<ref>{{cite web|url=https://www.bmuv.de/en/pressrelease/progressive-ban-on-mercury-containing-products |title= Progressive ban on mercury-containing products |date=January 2018 |access-date=2022-10-08 |publisher= bmuv }}</ref>

=== Recycling ===
{{See also|Fluorescent lamp recycling}}
Health and environmental concerns about mercury have prompted many jurisdictions to require spent lamps to be properly disposed of or recycled, rather than being included in the general waste stream sent to landfills. Safe disposal requires storing the bulbs unbroken until they can be processed.

In the [[United States]], most states have adopted and currently implement the federal [[Hazardous waste in the United States#Universal wastes|Universal Waste Rule]] (UWR).<ref name="epa27" /> Several states, including [[Vermont]], [[New Hampshire]], [[California]], [[Minnesota]], [[New York (state)|New York]], [[Maine]], [[Connecticut]] and [[Rhode Island]], have regulations that are more stringent than the federal UWR.<ref name="epa27">{{cite web |url=http://www.epa.gov/waste/hazard/wastetypes/universal/lamps/faqs.htm#27 |title=How are mercury-containing bulbs (called "lamps" in the regulations) regulated? |date=10 May 2013 |publisher=[[United States Environmental Protection Agency]] |access-date=18 June 2013}}</ref> Home-supply [[chain store]]s make free CFL recycling widely available.<ref>{{cite news |url=https://www.nytimes.com/2008/06/24/business/24recycling.html?em&ex=1214625600&en=8ddbcb7023c75243&ei=5087%0A |access-date=18 June 2013 |title=Home Depot Offers Recycling for Compact Fluorescent Bulbs |date=24 June 2008 |last=Rosenbloom |first=Stephanie |work=[[The New York Times]]}}</ref>

In the [[European Union]], CFLs are one of many products subject to the [[Waste Electrical and Electronic Equipment Directive|WEEE]] recycling scheme. The [[Price|retail price]] includes an amount to pay for recycling, and manufacturers and importers have an obligation to collect and recycle CFLs.

According to the Northwest Compact Fluorescent Lamp Recycling Project, because household users in the U.S. Northwest have the option of disposing of these products in the same way they dispose of other solid waste, in Oregon "a large majority of household CFLs are going to municipal solid waste". They also note the EPA's estimates for the percentage of fluorescent lamps' total mercury released when they are disposed of in the following ways: municipal waste landfill 3.2%, recycling 3%, municipal waste incineration 17.55% and hazardous waste disposal 0.2%.<ref>{{cite web |url=http://www.zerowaste.org/cfl/IMAGES_A/phase_I_rpt.pdf |title=Compact Fluorescent Lamp Recycling Project Phase I Draft Report Background Research and Program Options |url-status=dead |archive-url=https://web.archive.org/web/20070927040257/http://www.zerowaste.org/cfl/IMAGES_A/phase_I_rpt.pdf |archive-date=2007-09-27}}</ref>

The first step of processing CFLs involves crushing the bulbs in a machine that uses negative pressure ventilation and a mercury-absorbing filter or [[cold trap]] to contain mercury vapor. Many municipalities are purchasing such machines.{{Citation needed|date=May 2011}} The crushed glass and metal is stored in drums, ready for shipping to recycling factories.

=== Greenhouse gases ===
In some places, such as [[Quebec]] and [[British Columbia]] in 2007, [[central heating]] for homes was provided mostly by the burning of [[natural gas]], whereas electricity was primarily provided by [[hydroelectric]] power. An analysis of the impacts of a ban on incandescent light bulbs at that time introduced the notion that in such areas, heat generated by conventional electric light bulbs may have been significantly reducing the release of greenhouse gases from natural gas heating.<ref>{{cite conference |last1=Ivanco |first1=M. |last2=Karney |first2=B.W. |last3=Waher |first3=K.J. |title=To Switch, or Not to Switch: A Critical Analysis of Canada's Ban on Incandescent Light Bulbs |conference=[[IEEE]] Electrical Power Conference |date=25–26 October 2007 |pages=550–555 |doi=10.1109/EPC.2007.4520391}}</ref> Ivanco, Karney, and Waher estimated that "If all homes in Quebec were required to switch from (incandescent) bulbs to CFLs, there would be an increase of almost 220,000 [[tonne]]s in CO<sub>2</sub> emissions in the province, equivalent to the annual emissions from more than 40,000 automobiles."