Metabolite screening of aromatic amine hair dyes using in vitro hepatic models.

Aromatic amines and heterocyclic amines are widely used ingredients in permanent hair dyes. However, little has been published on their potential for oxidation via hepatic cytochrome P450s. Therefore, the authors screened nine such compounds for their potential to undergo oxidative metabolism in human liver microsomes. Toluene-2,5-diamine (TDA), p-aminophenol, m-aminophenol, p-methylaminophenol, N,N'-bis(2-hydroxyethyl)-p-phenylenediamine, and 1-hydroxyethyl-4,5-diaminopyrazole showed no evidence of oxidative metabolism. Oxidized metabolites of 4-amino-2-hydroxytoluene (AHT), 2-methyl-5- hydroxyethylaminophenol (MHEAP), and phenyl methyl pyrazolone (PMP) were detected, but there was no evidence of beta-nicotinamide adenine dinucleotide phosphate (NADPH)-dependent covalent binding to microsomal protein, suggesting that these are not reactive metabolites. Metabolism of AHT, MHEAP, PMP, and TDA was further studied in human hepatocytes. All these compounds underwent conjugation, but no oxidative metabolites were found. The results suggest that none of the hair dye ingredients tested showed evidence of hepatic metabolism to potentially biologically reactive oxidized metabolites.

Skin metabolism of aminophenols: human keratinocytes as a suitable in vitro model to qualitatively predict the dermal transformation of 4-amino-2-hydroxytoluene in vivo.

4-Amino-2-hydroxytolune (AHT) is an aromatic amine ingredient in oxidative hair colouring products. As skin contact occurs during hair dyeing, characterisation of dermal metabolism is important for the safety assessment of this chemical class. We have compared the metabolism of AHT in the human keratinocyte cell line HaCaT with that observed ex-vivo in human skin and in vivo (topical application versus oral (p.o.) and intravenous (i.v.) route). Three major metabolites of AHT were excreted, i.e. N-acetyl-AHT, AHT-sulfate and AHT-glucuronide. When 12.5 mg/kg AHT was applied topically, the relative amounts of each metabolite were altered such that N-acetyl-AHT product was the major metabolite (66% of the dose in comparison with 37% and 32% of the same applied dose after i.v. and p.o. administration, respectively). N-acetylated products were the only metabolites detected in HaCaT cells and ex-vivo whole human skin discs for AHT and p-aminophenol (PAP), an aromatic amine known to undergo N-acetylation in vivo. Since N-acetyltransferase 1 (NAT1) is the responsible enzyme, kinetics of AHT was further compared to the standard NAT1 substrate p-aminobenzoic acid (PABA) in the HaCaT model revealing similar values for K(m) and V(max). In conclusion NAT1 dependent dermal N-acetylation of AHT represents a 'first-pass' metabolism effect in the skin prior to entering the systemic circulation. Since the HaCaT cell model represents a suitable in vitro assay for addressing the qualitative contribution of the skin to the metabolism of topically-applied aromatic amines it may contribute to a reduction in animal testing.

Food safety hazards that occur during the production stage: challenges for fish farming and the fishing industry.

Seafood derived from wild fish as well as farmed fish has always been an important source of protein in the human diet. On a global scale, fish and fish products are the most important source of protein and it is estimated that more than 30% of fish for human consumption comes from aquaculture. The first part of this paper outlines the hazards and challenges associated with handling fish during farming and capture. The authors describe infectious agents that cause disease in fish as well as humans, zoonotic agents, intoxications due to bacteria and allergies caused by the consumption of fish. Although only a few infectious agents in fish are able to infect humans, some exceptions exist that may result in fatalities. However, the greatest risk to human health is due to the consumption of raw or insufficiently processed fish and fish products. The second part of the paper considers environmental contaminants in seafood that may pose a risk to human health, such as medicinal products and residues associated with aquaculture, persistent lipophilic organic compounds and metals (methyl-mercury, organotin). The authors include an updated overview of the various factors associated with farmed and captured fish that may cause risks to human health after consumption. Moreover, they discuss the challenges (in the widest sense) associated with handling fish during capture and farming, as well as those encountered during processing.

Colony establishment and maintenance of the eriophyid wheat curl mite Aceria tosichella for controlled transmission studies on a new virus-like pathogen.

High plains disease (HPD) is of serious economic concern for wheat and corn production, but little is known about the virus-like causal agent. In the field, HPD is often associated with Wheat streak mosaic virus (WSMV) and both pathogens are transmitted by the same eriophyid wheat curl mite, Aceria tosichella Keifer. The objective of this study was to develop methods for establishing and maintaining HPD-transmitting wheat curl mite colonies for their use in studies on HPD. Towards this goal, mite colonies from a mixed infection source were separated into colonies either (i). not viruliferous; (ii). only transmitting WSMV; or (iii). only transmitting HPD. Maintenance of these colonies required strictly separated incubator facilities and adaptation of mite-suitable transfer techniques to permit frequent passages of mites to healthy plants. The established colonies provided reliable sources of infective material to study the progression of HPD and/or WSMV in plants using sensitive immuno-detection assays. In conclusion, we have developed reliable methods with a poorly studied arthropod vector to examine the biology and properties of a new virus-like disease.

Development of an antibiotic resistance monitoring system in Hungary.

Because of the rapid development and spread of antimicrobial resistance it is important that a system be established to monitor antimicrobial resistance in pathogenic zoonotic and commensal bacteria of animal origin. Susceptibility testing of bacteria from carcasses and different samples of animal origin has been carried out in veterinary institutes for a long time but by an inconsistent methodology. The disc diffusion method proposed by the National Committee for Clinical Laboratory Standards (NCCLS) was introduced in all institutes in 1997. In order to obtain a coherent view of the antimicrobial resistance of bacteria a computer system was consulted, consisting of a central computer to store all data and some local computers attached to it through the network. At these local measuring stations computers are connected to a video camera, which displays the picture of Petri dishes on the monitor, and inhibition zone diameters of bacteria can be drawn with the mouse by the inspector. The software measures the diameters, evaluates whether or not the bacteria are sensitive, and stores the data. The evaluation is based upon the data of the NCCLS. The central computer can be connected to as many local computers with measuring stations as we wish, so it is suitable for an integrated system for monitoring trends in antimicrobial resistance of bacteria from animals, food and humans, facilitating comparison of the occurrence of resistance for each circumstance in the chain. It depends on the examiners which antibiotics they want to examine. Thirty-two different antibiotic panels were compiled, taking into consideration the active ingredients of medicinal products permitted for veterinary use in Hungary, natural resistance and cross-resistance, the mechanism of resistance and the animal species, i.e. which drugs were recommended for treatment in the given animal species, and the recommendations of the OIE Expert Group on Antimicrobial Resistance. The members of the panels can be changed any time, even during the measuring process. In addition to the inhibition zone diameters of bacteria the database also includes information about bacterial and animal species, the age of animals and the sample or organ where the bacteria are from. Since January 2001 the antibiotic susceptibility of E. coli, Salmonella, Campylobacter and Enterococcus strains isolated from the colons of slaughter cows, pigs and broiler chickens has also been examined. Each of the 19 counties of Hungary submits to the laboratory three tied colon samples from a herd of the above-mentioned animals every month.

Analysis of mechanisms associated with loss of infectivity of clonal populations of Borrelia burgdorferi B31MI.

Numerous studies have provided suggestive evidence that the loss of plasmids correlates with the loss of infectivity of the Lyme disease spirochetes. In this study we have further investigated this correlation. Clonal populations were obtained from the skin of a mouse infected for 3 months with a clonal population of Borrelia burgdorferi B31MI. The complete plasmid compositions of these populations were determined using a combination of PCR and Southern hybridization. The infectivities of clones differing in plasmid composition were tested using the C3H-HeJ murine model for Lyme disease. While several clones were found to be noninfectious, a correlation between the loss of a specific plasmid and loss of infectivity in the clones analyzed in this report was not observed. While it is clear from recent studies that the loss of some specific plasmids results in attenuated virulence, this study demonstrates that additional mechanisms also contribute to the loss of infectivity.

VraA (BBI16) protein of Borrelia burgdorferi is a surface-exposed antigen with a repetitive motif that confers partial protection against experimental Lyme borreliosis.

We have previously described the expression cloning of nine Borrelia burgdorferi antigens, using rabbit serum enriched for antibodies specific for infection-associated antigens, and determined that seven of these antigens were associated with infectious B. burgdorferi strain B31. One of these infection-associated antigens encoded a 451-amino-acid putative lipoprotein containing 21 consecutive and invariant 9-amino-acid repeat sequences near the amino terminus that we have designated VraA for virulent strain-associated repetitive antigen A. The vraA locus (designated BBI16 by The Institute for Genomic Research) maps to one of the 28-kb linear plasmids (designated lp28-4) that is not present in noninfectious strain B31 isolates. Subsequent PCR analysis of clonal isolates of B. burgdorferi B31 from infected mouse skin revealed a clone that lacked only lp28-4. Southern blot and Western blot analyses indicated that the lp28-4 and VraA proteins, respectively, were missing from this clone. We have also determined that VraA is a surface-exposed protein based on protease accessibility assays of intact whole cells. Furthermore, vraA expression is modestly derepressed when cells are grown at 37 degrees C relative to cells grown at 32 degrees C, suggesting that VraA is, in part, a temperature-inducible antigen. Homologues cross-reactive to B. burgdorferi B31 VraA, most with different molecular masses, were identified in several B. burgdorferi sensu lato isolates, including B. andersonii, suggesting that the immunogenic epitope(s) present in strain B31 VraA is conserved between Borrelia spp. In protection studies, only 8.3% of mice (1 of 12) immunized with full-length recombinant VraA fused to glutathione S-transferase (GST) were susceptible to infectious challenge with 10(2) B. burgdorferi strain B31, whereas naive mice or mice immunized with GST alone were infected 40% or 63 to 67% (depending on tissues assayed) of the time, respectively. As such, the partial protection elicited by VraA immunization provides an additional testable vaccine candidate to help protect against Lyme borreliosis.

Decreased infectivity in Borrelia burgdorferi strain B31 is associated with loss of linear plasmid 25 or 28-1.

Previous reports indicated a correlation between loss of plasmids and decreased infectivity of Borrelia burgdorferi strain B31, suggesting that plasmids may encode proteins that are required for pathogenesis. In this study, we expand on this correlation. Using the B. burgdorferi genomic sequence, we designed primers specific for each plasmid, and by using PCR we catalogued 11 linear and 2 circular plasmids from 49 clonal isolates of a mid-passage B. burgdorferi strain B31, initially derived from infected mouse skin, and 20 clones obtained from mouse skin infected with a low-passage isolate of B. burgdorferi strain B31. Among the 69 clones analyzed, nine distinct genotypes were identified relative to wild-type B. burgdorferi strain B31. Among the nine clonal genotypes obtained, only the 9-kb circular plasmid (cp9), the 25-kb linear plasmid (lp25), and either the 28-kb linear plasmid 1 or 4 (lp28-1 and lp28-4, respectively) were missing, in different combinations. We compared the infectivity of the wild-type strain, containing all known B. burgdorferi plasmids, with those of single mutants lacking either lp28-1, lp28-4, or lp25 and a double mutant missing both cp9 and lp28-1. The infectivity data indicated that B. burgdorferi strain B31 cells lacking lp28-4 were modestly attenuated in all tissues analyzed, whereas samples missing lp25 were completely attenuated in all tissues, even at the highest inoculum tested. Isolates without lp28-1 infected the joint tissue yet were not able to infect other tissues as effectively. In addition, we have observed a selection in vivo in the skin, bladder, and joint for cells containing lp25 and in the skin and bladder for cells containing lp28-1, indicating that lp25 and lp28-1 encode proteins required for colonization and short-term maintenance in these mammalian tissues. In contrast, there was no selection in the joint for cells containing lp28-1, suggesting that genes on lp28-1 are not required for colonization of B. burgdorferi within the joint. These observations imply that the dynamic nature of the B. burgdorferi genome may provide the genetic heterogeneity necessary for survival in the diverse milieus that this pathogen occupies in nature and may contribute to tropism in certain mammalian host tissues.

The many faces of Borrelia burgdorferi.

In this review we describe several genetic regulatory mechanisms adopted by the agent of Lyme disease, Borrelia burgdorferi, to sense and adapt to different host and environmental conditions either in vitro or in vivo. This regulation results in the increased or decreased synthesis of several proteins whose levels are believed to play key roles in the ability of B. burgdorferi to cycle between both arthropod and mammalian hosts. Moreover, the differential synthesis of these proteins serves to modulate the response of B. burgdorferito signals in the requisite host and may also, in some cases, function as virulence determinants of this spirochete. Elucidation of these mechanisms will help in the understanding of the pathogenicity of B. burgdorferi as well as aid in identifying proteins that are important during different stages of infection.

Comparison of protection in rabbits against host-adapted and cultivated Borrelia burgdorferi following infection-derived immunity or immunization with outer membrane vesicles or outer surface protein A.

In this study, infection-derived immunity in the rabbit model of Lyme disease was compared to immunity following immunization with purified outer membrane vesicles (OMV) isolated from Borrelia burgdorferi and recombinant outer surface protein A (OspA). Immunization of rabbits with OMV isolated from virulent strain B31 and its avirulent derivative B313 (lacking OspA and DbpA) conferred highly significant protection against intradermal injection with 6 x 10(4) in vitro-cultivated virulent B. burgdorferi. This is the first demonstration of protective immunogenicity induced by OMV. While immunization with OspA and avirulent B31 OMV provided far less protection against this challenge, rabbits with infection-derived immunity were completely protected. Protection against host-adapted B. burgdorferi was assessed by implantation of skin biopsies taken from rabbit erythema migrans (a uniquely rich source of B. burgdorferi in vertebrate tissue) containing up to 10(8) spirochetes. While all of the OMV- and OspA-immunized rabbits were fully susceptible to skin and disseminated infection, rabbits with infection-derived immunity were completely protected. Analysis of the antibody responses to outer membrane proteins, including DbpA, OspA, and OspC, suggests that the remarkable protection exhibited by the infection-immune rabbits is due to antibodies directed at antigens unique to or markedly up-regulated in host-adapted B. burgdorferi.

Concordant prune belly syndrome in monozygotic twins.

We report 2 cases of concordant prune belly syndrome occurring in monozygotic twins. In addition to suggesting a genetic basis for this disease, our 12-year follow-up of these cases illustrates that these patients with an otherwise poor prognosis can have normal growth, development, and renal function with appropriate treatment.

Positive CSF HSV PCR in patients with GBM: a note of caution.

Because two patients with temporal lobe glioblastomas had herpes simplex (HSV) DNA detected in CSF using PCR at the time of their presentation, we reviewed our laboratory's experience and performed PCR on a bank of 159 frozen CSF samples from patients with glioblastoma multiforme and other neurologic disorders. Based on the inability to detect HSV in any other tumor sample, we conclude that the positive HSV PCR in our two index patients most likely represented false-positive results. A diagnosis of HSE should not be made by PCR alone when the clinical presentation is atypical.

A new transthyretin variant (Ser23Asn) associated with familial amyloidosis in a Portuguese patient.

The detection and characterization of a new transthyretin (ATTR) variant, Ser23Asn, associated with cardiomyopathy in a Portuguese patient with familial amyloidosis is described. Isoelectric focusing (IEF) of serum from the propositus demonstrated heterozygosity for the presence of wild type and variant ATTR. A combination of mass spectrometric (MS) analyses, including electrospray ionization mass spectrometry (ESI MS), high performance liquid chromatography (HPLC)/ESI MS and matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) performed on the serum-derived TTR were used to identify and locate the amino acid replacement in the variant protein. Genetic mutation analysis by DNA sequencing and allele-specific PCR confirmed this finding.

Cloning and molecular characterization of plasmid-encoded antigens of Borrelia burgdorferi.

Thirteen independent clones that encode Borrelia burgdorferi antigens utilizing antiserum from infection-immune rabbits were identified. The serum was adsorbed against noninfectious B. burgdorferi B31 to enrich for antibodies directed against either infection-associated antigens of B. burgdorferi B31 or proteins preferentially expressed during mammalian infection. The adsorption efficiency of the immune rabbit serum (IRS) was assessed by Western immunoblot analysis with protein lysates derived from infectious and noninfectious B. burgdorferi B31. The adsorbed IRS was used to screen a B. burgdorferi expression library to identify immunoreactive phage clones. Clones were then expressed in Escherichia coli and subsequently analyzed by Western blotting to determine the molecular mass of the recombinant B. burgdorferi antigens. Southern blot analysis of the 13 clones indicated that 10 contained sequences unique to infectious B. burgdorferi. Nucleotide sequence analysis indicated that the 13 clones were composed of 9 distinct genetic loci and that all of the genes identified were plasmid encoded. Five of the clones carried B. burgdorferi genes previously identified, including those encoding decorin binding proteins A and B (dbpAB), a rev homologue present on the 9-kb circular plasmid (cp9), a rev homologue from the 32-kb circular plasmid (cp32-6), erpM, and erpX. Additionally, four previously uncharacterized loci with no known homologues were identified. One of these unique clones encoded a 451-amino-acid lipoprotein with 21 consecutive, invariant 9-amino-acid repeats near the amino terminus that we have designated VraA (for "virulent strain-associated repetitive antigen A"). Since all the antigens identified are recognized by serum from infection immune rabbits, these antigens represent potential vaccine candidates and, based on the identification of dbpAB in this screen, may also be involved in pathogenic processes operative in Lyme borreliosis.

A new amyloidogenic transthyretin variant (Val122Ala) found in a compound heterozygous patient.

A new TTR variant, Val122Ala, was characterized in an individual who carried the Gly6Ser polymorphism on the opposite allele. The main clinical feature of this familial transthyretin amyloidosis (ATTR) variant is extensive cardiomyopathy. The detection and characterization of the variant were performed using a combination of isoelectric focusing (IEF), restriction fragment length polymorphism (RFLP), immunoprecipitation, electrospray ionization mass spectrometry (ESIMS), HPLC (high performance liquid chromatography)/ESIMS, and matrix-assisted laser desorption/ionization mass spectrometry (MALDIMS). The results were confirmed by DNA analysis. The propositus has a brother who carries the new variant but not the polymorphism.

Characterization of transthyretin mutants from serum using immunoprecipitation, HPLC/electrospray ionization and matrix-assisted laser desorption/ionization mass spectrometry.

A mass spectrometry approach for the detection and identification of variants of the plasma protein transthyretin (TTR) is presented. The single amino acid substitutions found in TTR are closely associated with familial transthyretin amyloidosis (ATTR), a hereditary degenerative disease. A definitive diagnosis of ATTR relies on the detection and identification of TTR variants. The approach presented here is based on isolation of serum TTR using immunoprecipitation. The detection of the variant is achieved by mass measurement of the intact protein with electrospray ionization mass spectrometry (ESIMS). The liquid chromatography/ESIMS analysis of the tryptic digest of the protein followed by subsequent matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry and MALDI postsource decay of the relevant recovered chromatographic fraction containing the variant peptide allows the identification of unknown variants. The method was successfully tested using serum from ATTR patients with known variants (Val30-->Met and Val122-->Ile). A new TTR variant, Ser23-->Asn, was detected and identified using the above method where isoelectric focusing and restriction enzyme analysis failed to identify the nature of the variant.

A simple screening test for variant transthyretins associated with familial transthyretin amyloidosis using isoelectric focusing.

Variant forms of the plasma protein transthyretin (TTR) are associated with the most frequently occurring type of familial systemic amyloidosis. Organ system involvement in transthyretin type amyloidosis (ATTR) is often similar to that which occurs in light chain amyloid disease (AL). The proper diagnosis of ATTR is important since treatment (liver transplantation) differs from that in AL (chemotherapy). We present a two-step test to screen sera for variant TTRs using non-denaturing gel electrophoresis performed in 7.5% acrylamide (PAGE) followed by isoelectric focusing (IEF) between pH 4.0 and 7.0 in 2.5 M urea. Serum samples from 110 patients with amyloidosis and their relatives were tested using this IEF technique and compared to genetic mutation results. Sera from patients with ATTR who underwent liver transplantation were also examined prior to and following surgery. IEF analysis showed the presence of both wild-type and variant TTR in 74 of the 110 serum samples tested. Genomic DNA from peripheral blood was used to identify TTR gene mutations in 77 of the 110 patients. Fifteen variants including Val122Ile, preponderant in the African-American population, could be demonstrated by IEF. The sensitivity of IEF was 96% (74/77) and the specificity was 100% (33/33). The predictive values for a positive or negative result were 100% (74/74) and 92% (33/36), respectively. There were no false-positive results and 4% (3/77) false-negative results. In sera from patients with ATTR who underwent liver transplantation, variant TTR was detected by IEF before, but not after, surgery. A simple, accurate, sensitive method is presented as a useful screening test for variant transthyretins associated with ATTR.

Isolation and characterization of the outer membrane of Borrelia hermsii.

The outer membrane of Borrelia hermsii has been shown by freeze-fracture analysis to contain a low density of membrane-spanning outer membrane proteins which have not yet been isolated or identified. In this study, we report the purification of outer membrane vesicles (OMV) from B. hermsii HS-1 and the subsequent identification of their constituent outer membrane proteins. The B. hermsii outer membranes were released by vigorous vortexing of whole organisms in low-pH, hypotonic citrate buffer and isolated by isopycnic sucrose gradient centrifugation. The isolated OMV exhibited porin activities ranging from 0.2 to 7.2 nS, consistent with their outer membrane origin. Purified OMV were shown to be relatively free of inner membrane contamination by the absence of measurable beta-NADH oxidase activity and the absence of protoplasmic cylinder-associated proteins observed by Coomassie blue staining. Approximately 60 protein spots (some of which are putative isoelectric isomers) with 25 distinct molecular weights were identified as constituents of the OMV enrichment. The majority of these proteins were also shown to be antigenic with sera from B. hermsii-infected mice. Seven of these antigenic proteins were labeled with [3H]palmitate, including the surface-exposed glycerophosphodiester phosphodiesterase, the variable major proteins 7 and 33, and proteins of 15, 17, 38, 42, and 67 kDa, indicating that they are lipoprotein constituents of the outer membrane. In addition, immunoblot analysis of the OMV probed with antiserum to the Borrelia garinii surface-exposed p66/Oms66 porin protein demonstrated the presence of a p66 (Oms66) outer membrane homolog. Treatment of intact B. hermsii with proteinase K resulted in the partial proteolysis of the Oms66/p66 homolog, indicating that it is surface exposed. This identification and characterization of the OMV proteins should aid in further studies of pathogenesis and immunity of tick-borne relapsing fever.

In vitro reproductive toxicity of polychlorinated biphenyl congeners 153 and 126.

This study was conducted to investigate the applicability of an in vitro technique for maturation, fertilization, cleavage, and growth to blastocysts of bovine oocytes to investigate reproductive toxicologic effects. During maturation, the oocytes were exposed to the di-ortho-substituted PCB congener 2,2',4,4',5,5'-CB (PCB 153) in the three concentrations 0.84 ng/mL, 8.4 ng/mL, and 84 ng/mL or to the non-ortho-substituted PCB congener 3,3'4,4',5-CB (PCB 126) in the three concentrations 1.006 pg/mL, 10.06 pg/mL, and 100.6 pg/mL and compared with control groups. PCB 153 had no effect on maturation but resulted in a reduced proportion of oocytes that cleaved at the highest concentration. There were no differences in blastocyst development among groups. PCB 126 resulted in a reduction in maturation percentage at the highest concentration and in blastocyst development at all concentrations. These results demonstrated adverse effects of PCB congeners on bovine oocytes and showed that this system can be used to evaluate toxic effects on oocytes and preimplantation-stage embryos.

Antihistamine-containing cough/cold medications present a low hazard in pediatric accidental exposure incidents: analysis of Poison Control Center data.

We studied accidental exposure to pediatric cough/cold medications in children under 6-y-of-age to determine whether the presence of an antihistamine (chlorpheniramine) in the product increased the likelihood for adverse outcomes. General accidental exposure cases reported to the American Association of Poison Control Centers (AAPCC) during 1988-1992 were analyzed for specific over-the-counter cough/cold pediatric products containing identical concentrations of active ingredients except for the presence or absence of chlorpheniramine. These case reports were evaluated for differences in medical outcome, symptom assessment, management site and therapy, as coded by poison control centers participating in the AAPCC Toxic Exposure Surveillance System. A total of 10,289 cases of accidental exposures were evaluated for the specific products included in this analysis. While these cases represented a small percentage of total exposures to these products (approximately 3% of total cases in children under 6-y-of-age reported to the AAPCC for all cough/cold medications during 1988-1992), they provided a unique opportunity to evaluate the impact of the antihistamine component of the formulation. This study demonstrated that the presence of chlorpheniramine did not affect the medical outcome or the extent to which symptoms were reported. Additionally, similar percentages of exposures for these 2 products were managed at the site of the incident, and required either no therapy or only required fluids and observation. There were no notable differences in the percentage of cases which involved more aggressive treatment procedures (activated charcoal, cathartic, lavage). This analysis demonstrates that over-the-counter cough/cold medications containing chlorpheniramine present low potential for hazard in cases of accidental ingestions in young children and do not show an increased likelihood for adverse outcomes of accidental exposures compared to cough/cold medications not containing this antihistamine.