nd huged asAs aen hoany f
(Ahn et al., 2008).This level of uncertainty introduces a formidable challenge for
product development scientists who aim to formulate productswith superior human health and environmental safety proles. Dueto the complexity of biological systems, establishing causal
One of the major points of opposition to the use of the PP,particularly in product development, is that its application stiesinnovation by requiring proof of safety prior to introducing a newtechnology (Kriebel et al., 2001). In the case of pharmaceuticaldevelopment, the benet of innovation can often outweigh the riskor hazard associated with uncertain effects. For example, innova-tion in treatment for terminal illnesses such as stage IV cancers orHIV/AIDS can result in saving or signicantly extending a patientslife, therefore, the benet of remission or cure outweighs the risk of
* Tel.: 1 802 658 3773x516; fax: 1 802 658 1771.
Contents lists availab
Journal of Clean
Journal of Cleaner Production 19 (2011) 429e437E-mail address: email@example.com cleaning product ingredients and negative environmentaland human health effects such as eutrophication (Conley et al.,2009), air pollution (Nazaroff and Weschler, 2004; Destaillatset al., 2006; Kwon et al., 2008), and endocrine disruption(Diamanti-Kandarakis et al., 2009; Rudel et al., 2003) have hada signicant impact on the consumer view of household productsafety. In addition to the negative relationships that have beenestablished, there are also ingredients that are suspected of havingunintended negative consequences but for which direct relation-ships to health and the environment have not been demonstrated
The most widely used principle to guide such characterization inthe face of scientic uncertainty is the Precautionary Principle (PP)which can be summarized as follows: when an activity raises thethreat of harm to human health and the environment, precau-tionary measures should be taken even if some cause and effectrelationships are not fully established scientically(Rafferspergerand Tickner, 1996). By taking preventive action in the face ofuncertainty and developing alternatives, the PP prevents additionalexposures and can protect human health and the environmentdespite the absence of conclusive evidence of a negative effect.Precautionary principleDisinfectant
Protecting the environment aresponsible consumerism has emerbuyer behavior (Thogersen, 2006).demand for and availability of gresignicantly increased. Although mchange, the direct relationships de0959-6526/$ e see front matter 2010 Elsevier Ltd.doi:10.1016/j.jclepro.2010.07.008man health throughan important shift inresult, both consumerusehold cleaners haveactors inuenced thisated between conven-
relationships between an ingredient and an ecological or physio-logical effect requires such rigorous inquiry that by the timea causeeeffect relationship is established and accepted, myriadexposures have occurred which could have been prevented.Managing scientic uncertainty in ingredient safety assessmentsrequires a well-designed system of evaluation and ranking tocategorize the severity of potential hazards that ingredients andformulated products pose to consumers and to the environment.Toxic chemicalsHousehold cleaningProduct development 2010 Elsevier Ltd. All rights reserved.Applying the precautionary principle todevelopment
Cara A.M. Bondi*
Research & Development, Seventh Generation, Inc., 60 Lake Street, Burlington, Vermont
a r t i c l e i n f o
Article history:Received 25 January 2010Received in revised form8 July 2010Accepted 8 July 2010Available online 16 July 2010
a b s t r a c t
Hazardous chemicals arelished associations with adamage. Although these asdescribes the applicationingredient for a botanical dtraditional disinfectant actnot stie innovation and f
journal homepage: wwwAll rights reserved.onsumer household cleaning product
asive in household disinfectant products. Many ingredients have estab-e and chronic human health conditions as well as with environmentaliations are suggested but not proven, they are of great concern. This articlethe precautionary principle to the selection of an anti-microbial activefectant when signicant uncertainty exists around the hazard and risk ofingredients. We show that application of the precautionary principle doestates a responsible approach to product development.
le at ScienceDirect
evier .com/locate/ jc lepro
Protection Agency, are classied as pesticides, and have highly
er Pregulated claims it may be a function of the inability to commu-nicate human health or environmental safety claims that has pre-vented the greening of the category. Notwithstanding theconstraints imparted by the regulations, green consumers are facedwith a situation in which they must use a conventional anti-microbial pesticide if they desire to kill microorganisms in theirhomes. Considering the green consumers awareness aroundchemical exposure they are faced with a disinfection dilemma:protecting their family from germs or protecting their family frompotentially harmful chemical exposures. As such, developing a hardsurface disinfectant formulated with safer active and inert ingre-dients would not only present a signicant innovation in the greenand disinfectant spaces, but would also provide a solution to thisconsumer dilemma.
In January 2010 this concept became a reality with the intro-duction of an EPA registered disinfectant that kills germs botani-cally. This article describes the application of the PP toanti-microbial ingredient selection for and development of thisnatural hard surface disinfectant, and describes how its applicationin consumer product development can act to foster innovation andproduce viable alternatives to potentially hazardous chemistries.
2. Determining uncertainty: anti-microbial active ingredients
Of the registered disinfectants available in the consumermarket, the most common active ingredients are quaternaryammonium compounds and sodium hypochlorite. Another ingre-dient, Triclosan, is usedmore predominately in anti-microbial handwashes but is also utilized in several registered surface disinfec-tants. A review of the scientic literature reveals evidence whichsuggests relationships between these conventional disinfectantactive ingredients and serious human health and environmentalissues such as asthma and respiratory sensitization (Bernstein et al.,1994; Burge and Richardson, 1994; Leroyer et al., 1998; Nickmilderet al., 2007; Nielsen et al., 2007; Preller et al., 1996; Purohit et al.,2000; Shakeri et al., 2008; Zock et al., 2001; Medina-Ramonet al., 2005), air pollution (Kwon et al., 2008; Odabasi, 2008; Fisset al., 2007), bioaccumulation and reproductive toxicity in wildlife(Fair et al., 2009; Fry, 2005), and bacterial resistance (Levy, 2001;Gaze et al., 2005; Russell et al., 1998; Sundheim et al., 1998;Aiello and Larson, 2003). However, causal relationships have notbeen denitively established. As such, in considering active ingre-unknown adverse effects. Conversely, from the perspective ofa green household cleaning formulation the risk of harming humanhealth and/or the environment far outweighs the benet ofproviding consumers with the latest innovation in householdcleaning. In addition, launching a product that is later found to bewholly or in part unsafe for health or the environment contradictsthe central tenant of green chemistry, which is to provide saferalternatives. This does not suggest that innovation is not the goal ofgreen product developers; however, safety as dened by thedeveloper supersedes innovation as a priority. For this reason, theearly green product lines followed a less bad philosophy in orderto provide alternatives to existing products on the market. Due tothe increase in demand for sustainable, safe products the markethas changed and product developers have more raw materialoptions thereby evolving green product development from thepursuit of less bad to the pursuit of true innovation.
Despite the introduction of green offerings in almost everyhousehold cleaner category, disinfectants and sanitizers have hadno signicant green alternatives introduced to date. As theseproducts are required to be registered with the US Environmental
C.A.M. Bondi / Journal of Clean430dients for a natural surface disinfectant with a superior humanhealth and environmental safety prole evaluating the uncertaineffects of these ingredients is necessary.
Used as an anti-microbial since the 1960s, triclosan (TCS) isa broad spectrum anti-microbial commonly found in anti-bacterialproducts spanning personal and household care. TCS prevents fattyacid synthesis in the cell membrane by inhibiting the activity of theNADH-dependent enoyl-acyl carrier protein reductase (FabIenzyme), or its homolog, the InhA gene (McMurry et al., 1998, 1999;Heath and Rock, 2000; Slyden et al., 2000; Parikh et al., 2000;Chauncheun et al., 2001; Heath et al., 1998; Hoang and Schwezer,1999; Heath et al., 2000). This mechanism of action is similar tosome antibiotics and research suggests that TCS may confer cross-resistance to antibiotics (Aiello and Larson, 2003; McMurry et al.,1988). However, the true potential for TCS containing householdproducts to cause cross-resistance to antibiotics is unknown.
TCS has been linked to hormone disruption in animals, speci-cally sh, frogs, and rats (Ciniglia et al., 2005; Ishibashi et al., 2004;Matsumura et al., 2005; Zorrilla et al., 2009; Foran et al., 2000;Veldhoen et al., 2006). More recently, studies suggest that TCSmay have the potential to disrupt the endocrine system in humanswhich is of signicant concern as the chemical is essentially ubiq-uitous and has beenmeasured in breast milk at levels of 2000 mg/kglipid and 3790 mg/L in human urine (Ahn et al., 2008; Allmyra et al.,2006; Calafat et al., 2008; Gee et al., 2008; Chen et al., 2007;Adolfsson-Erici et al., 2002). However, a causeeeffect relationshipbetween TCS and endocrine disruption has not been denitivelyproven in humans or in wildlife. Therefore, the risk of endocrinedisruption resulting from human or animal exposure to TCS con-taining cleaning products is unknown.
Due to its structural similarity to toxic and environmentallypersistent compounds such as dioxins, the secondary reactions andenvironmental fate of TCS have been of special interest. Forexample, one study showed that TCS in formulation has the abilityto react with chlorine in tap water to produce 2,4-dichlorophenol,2,4,6-trichlorophenol, and chloroform although the risk introducedby these exposures was not determined (Fiss et al., 2007). In otherstudies, the photodegredation of TCS also resulted in the formationof 2,4-dichlorophenol as well as other toxic compounds such as, 2,8dichlorodibenzodioxin, and dichlorohydroxydiphenyl (Latch et al.,2003; Sanchez-Prado et al., 2006). As several reports show thatTCS is commonly found in sources that are directly exposed tosunlight, such as surface water and streams, it can be suggested thepresence of TCS increases the risk of exposure to its toxic degra-dation products (Hua et al., 2005; Kolpin et al., 2002). In addition tostreams and surface water, there have been reports that TCSpresent in wastewater is difcult to remove, remains after sewagetreatment, and also remains in sludge and biosolids (Chu andMetcalfe, 2007; Heidler and Halden, 2007). However, the pres-ence of TCS degradation products in the environment has not beenconnected to the presence of TCS in the environment; therefore, itis uncertainwhat proportion of the environmental load is the resultof degradation of TCS versus other sources. In addition, no rela-tionships have been established regarding the presence of TCS inwastewater, sludge, and biosolids to specic human health orenvironmental issues.
2.2. Quaternary ammonium compounds
Among the most common biocides found in household disin-fectants are quaternary ammonium compounds (QACs). While themechanism of action can differ according to structure and, specif-
roduction 19 (2011) 429e437ically, chain length, QACs typically kill bacteria by inserting
er Pthemselves into the microorganisms lipid bilayer thereby causinga membrane disruption that results in the leakage of intracellularconstituents (Ioannou et al., 2007). The antibiotic resistancepotential of QACs has been well characterized and several resis-tance genes have been identied (Chapman, 2003). The QACresistance genes are found on mobile genetic elements that canspread through horizontal genetic transfer, but serial transfer hasalso been reported. Despite the well characterized resistance genes,the presence and expression of such genes do not necessarily conferresistance to antibiotics and disinfectants and, as such, QAC disin-fectants continue to be a commonly used anti-microbial technologyand have not been identied as a major risk for causing resistance(McCay et al., 2010).
The most signicant area of debate related to QACs is the sug-gested potential for exposure to result in respiratory sensitizationand asthma. Several studies have demonstrated the relationshipbetween prolonged exposure to QACs and occupational asthma orrespiratory sensitization (Bernstein et al., 1994; Burge andRichardson, 1994; Preller et al., 1996; Purohit et al., 2000;Rosenman et al., 2003; Zock et al., 2007). However, despite thesignicant evidence in professional settings, the risk of developingasthma or respiratory sensitization from using disinfectants withQAC active ingredients has not been described in a householdsetting. Overall, no denitive link between QAC exposure andrespiratory effects has been established in professional or domesticsettings. However, the strong correlation between exposure, illnessand the biochemical evidence that QACs are immune adjuvantssuggests that certain health effects such as the dramatic increasesin pediatric asthma and dermatitis may be related to QAC exposure(Militello et al., 2006; Akinbami and Schoendorf, 2002).
Reproductive and developmental issues related to QAC exposurehave also been reported (Maher, 2008). In one report, a murinecolony experienced signicant developmental and reproductiveeffects after transferring research institutions. Upon careful exam-ination of all variables, the investigator determined that the changeto a QAC disinfectant to clean housing for the colony was the sourceof the breeding problem. After transitioning back to a non-QACdisinfectant the breeding issues within the colony resolved (Maher,2008). While these results have not been reproduced in humansand QACs have not been specically identied as human repro-ductive or developmental toxicants, there are several epidemio-logical studies that show signicant associations betweenoccupation as a cleaning person/biocide exposure and increasedodds of birth defects including cleft palate and neural tube defectssuch as spina bida (Bl...