the foodindustry,particularlyin the USA.A typical definition of a sanitiser is a substancethat reduces microbial contamination on inanimate surfaces to levels that are consideredsafefroma publichealthstandpoint' (Grab and Bennett, 2001).Sanitisers are usedby the foodprocessing,foodhandling, preparation and service industries, and milk (i.e.dairy)and beverage-producing (including breweries, soft drink and canning facilities) industries.Sanitisers are usually divided into two groups, dependingon whether or not theycomeinto contact withfood.This is particularly important, since the testingprotocolsand the required efficacy differdepending upontheirusage.Disinfectants,sterilants'
and antisepticsare usedin the healthcareenvironment (e.g.hospital, dental,
veterinary,nursing,day-care serviceproviders)to preventand control infection.
As for sanitisers, theirrequired microbicidalefficacydependsupontheirusage.
Three levelsof disinfectionare usuallyconsidered;high-,intermediate and low-
level, and theyare definedaccording to the potentialrisk of microbial infection
to patients(Rutala and Weber, 2004).
Biocides usedfor disinfectionand sanitisation
Bothdisinfectantsand sanitisersare usedfor reducingmicrobial contamination
frominanimate surfaces to an acceptable,safe level.Theirantimicrobial efficacy
is thereforeof prime importance. Thereare mainly six distinct classesof
sanitisers:chlorine,iodophors,quaternaryammonium compounds(QACs), acid±
anionic sanitisers, carboxylic acidand peroxy-acid compounds. Additional
biocides can be usedin disinfectantformulations,mainly aldehydes(e.g.glutar-
aldehyde,ortho-phthalaldehyde), phenolics (e.g.triclosan),biguanides (e.g.
chlorhexidine) and alcohols. All these agentsare chemicallydistinct, although
some havesimilar mechanisms of action.For example, QACs,biguanidesand
phenolics are all membrane-active agents (Russell,2001).In additionsome
biocides can be usedin combination suchas chlorhexidine and alcohols.
Otheruses:`sterilisation', antisepsis and preservation
Biocidesare usedfor a rangeof applicationsand play an importantrole in infection
controlpoliciesin the healthcareenvironment.Somehighlyreactivebiocides,such
as alkylating(e.g. glutaraldehyde,ortho-phthalaldehyde)and oxidisingagents(e.g.
peraceticacid,hydrogenperoxide)are usedfor high-leveldisinfectionof critical
items(e.g.endoscopes).Usuallytheiruse is associatedwithparticularmedical
equipments such as automated washer-disinfectors (AWD) which combine
preliminarycleaning,disinfectionand rinsing(Fraise,2004b).
Biocides are also extensively used for antisepsis. Hand-washing is an
essentialpart of infectioncontrol policiesin the healthcare environment and is
associated with goodhygiene and goodmanufacturingpractice in various
industries.Appropriate usageof antisepticsand complianceby the end usersare
essential.In the healthcare environmentcomplianceto hand-washingpolicies
has beenassociatedwith a reduction in cross-infection(Boyceand Pittet,2002).
The preservation of foodstuffsand waterby biocides is one of the oldest
documentedusesof chemical biocides (e.g.the use of copperpotsto preserve
644 Handbookof hygiene controlin the foodindustry