Studies on the acute toxicity primary irritancy and genotoxic potential of 1,3,5-triacryloylhexahydro-s-triazine (TAHT)

TAHT (1,3,5-triacryloylhexahydro-s-triazine), a reactive chemical coupling agent, was highly toxic following a single peroral dose of an aqueous suspension (10% w/v) to Wistar rats, or following application of TAHT in dichloromethane (DCM) solution (10% w/v) to covered skin of New Zealand rabbits. It was moderately toxic when applied dermally as an aqueous paste. Ocular contact with 25 mg of TAHT in a 5% aqueous suspension, or of 0.5 mg of TAHT in a 10% (w/v) solution in DCM, produced severe corneal damage, iritis and blepharo-conjunctivitis. A 30-min exposure of uncovered rabbit skin to 1 mg of TAHT in a 10% (w/v) aqueous suspension produced only slight skin irritation. However, 24-h exposures to TAHT on covered skin produced erythema, edema, ecchymoses, scabs, and death depending upon dosage and vehicle. In vitro genotoxicity studies revealed no positive effects upon gene mutations (HGPRT locus) or on sister chromatid exchanges (SCEs) of CHO cells exposed to TAHT with and without a rat-liver S9 metabolic activation system. TAHT did not increase the levels of [3H]thymidine incorporation in a test for unscheduled DNA synthesis with primary rat hepatocytes. In contrast, substantial increases in the number of chromosome breaks and rearrangements were observed in chromosome preparations used for the SCE analyses. The clastogenic activity of TAHT was confirmed in an in vitro chromosome aberration test with CHO cells. Treatment-related increases in chromosome breakage were observed at two independent sampling times and positive effects did not depend upon the presence or absence of a metabolic activation system. Clastogenic activity of TAHT was also demonstrated in vivo in a micronucleus test using mouse peripheral polychromatic erythrocytes. Significant, treatment-related increases in micronucleated polychromatic erythrocytes were obtained at two of three sampling times. The high degree of mammalian toxicity, severe eye irritancy and the in vitro and in vivo clastogenicity indicate that TAHT should be handled as a hazardous material using suitable caution and protective equipment.

[Toxicological studies on sophorolipid derivatives. (II). Subacute toxicity study of polyoxypropylene (12) [2'-0-beta-D-glucopyranosyl-beta-D-glucopyranosyl) oxy-] fatty acid ester-]

Five groups of 12 male and 12 female rats each were fed diets containing 0, 0.06, 0.25, 1.00 and 4.00% PSL for a period of one month. Food consumption of PSL-fed groups did not differ from that of control. Urinalysis and autopsy findings were within normal in every group of rats treated. With 4.00% in the diet, body weight gain was significantly retarded and water consumption was increased, and soft stool occurred. In the hematological examination, decrease of red blood cells and increase of white blood cells were observed at the levels of 1.00 and 4.00% PSL. Changes of white blood cell differentials were also seen at the same levels. Serum Na+ concentration was slightly decreased at the 0.25, 1.00, 4.00% levels and serum glucose was also decreased at the 1.00, 4.00% levels, but the values were within the normal limits. Significant increase of relative liver weight, without histopathological changes, was observed at the 4.00% level. Histopathological examination revealed slight erosion, necrosis or intestinitis in small intestine, at the levels of 0.25, 1.00, 4.00% PSL. It was considered that these findings were attributed to the irritation potential of PSL or its metabolite. These results indicated that the non-effect level was 0.06% (53 mg/kg/day) and the level causing no toxicological effect was 0.25% (208 mg/kg/day), but no deleterious effects was observed in the levels greater than 0.25%.

[Toxicological studies on sophorolipid derivatives. (I). Acute toxicity, eye irritation, primary skin irritation, skin sensitization, phototoxicity, photosensitization, mutagenicity of polyoxypropylene (12) [(2'-0-beta-D-glucopyranosyl-beta-D-glucopyranosyl)oxy-] fatty acid ester-]

Acute toxicity, eye irritation, primary skin irritation, skin sensitization, phototoxicity, photosensitization and mutagenicity of sophorolipid derivatives were studied in rats, mice, rabbits, guinea pigs and Salmonella typhimurium strains. The acute oral toxicity of sophorolipid (SL) which Torulopsis bombicola produces, and its derivatives (PSL, Ethyl-SL and Oleyl-SL) were shown to be very low. The LD50 values of PSL ranged from 10 g/kg to 16 g/kg on oral administration in rats and mice, and from 5.8 g/kg to 6.6 g/kg on subcutaneous administration in mice. The oral LD50 values of Ethyl-SL and Oleyl-SL were estimated to be greater than 15 g/kg and that of SL was 12.5 g/kg. In eye irritation study, PSL failed to produce any reactions at 50% concentration even when the rabbit eye was not subsequently washed. SL, Ethyl-SL, Oleyl-SL and Tween 20 were "no irritant" or "slight irritant" to the rabbit eye at 20% concentration. PSL showed no irritancy to both the intact and abraded guinea pig skin at 50% concentration. And in other examinations, it was also indicated that PSL had no potentials of skin sensitization, phototoxicity and photosensitization in guinea pigs and had no potentials of mutagenicity in Salmonella typhimurium TA98 and TA100.

[Contact eczemas in housewives]

Housewives come into contact with a great number of irritating and allergenic substances on a daily basis. Contact dermatitis of the hands is a common result, caused more frequently by irritation than by allergy. In this review, the sources of contact allergens encountered in domestic work are shown and their relevance to sensitization and elicitation of hand excema is discussed.

Hazard evaluation of monochloroacetone

Monochloroacetone was introduced in 1914 as a war gas, and presently it has a number of uses as a chemical intermediate. Apart from its biological properties as a lacrimator and vesicant, it is not a well-studied compound toxicologically. A series of acute toxicity studies were done using different routes of administration. An Ames mutagenicity test also was performed. These data were compared to manufacturing use information and data published in the literature. It is recommended that direct contact with liquid and vapor be prevented through strict engineering controls and that air concentrations be kept below 1 ppm as a ceiling concentration.

[The irritative potency of disinfectants]

The cumulative irritation power examined of some chemical disinfectants usual in the GDR. The recognition of irritation time (IT50) demonstrates in the animal experiment (pigs) and in probands with the epidemiological reality a good accordance.

[Acute toxicity test on dermal application of NT-1 tape and 10% nitroglycerin (NT-1 ointment)]

An acute toxicity of NT-1 tape was investigated in mice, rats and rabbits, and also an acute toxicity of NT-1 ointment in rabbits. An irritation of NT-1 tape was investigated in rabbits. Dead animals treated with NT-1 tape or ointment were not observed in reliable maximum administration dose of 0.88 mg/body as GTN (nitroglycerin) in mice (male; about 29.1 mg/kg, female; about 35.2 mg/kg), of 3.96 mg/body as GTN in rats (male; about 26.0 mg/kg, female; about 28.9 mg/kg) and of 480 mg/kg as GTN in rabbits. There were not toxic signs in mice and rats. The below findings were observed in rabbits treated mainly with NT-1 ointment: decreased spontaneous activity, decreased reactivity to various stimuli such as sound and touch, and behavior of binding food box. However, the rabbits recovered from those abnormal behavior in a day. Any body weight changes and any autopsy findings attributable to NT-1 tape or ointment were not observed in mice, rats and rabbits. The effects on ECG were not observed in rabbits. The GTN absorption ratio in rabbits treated with NT-1 ointment was thought to be 60-70% from GTN residual ratio. The skin irritation was not observed in rabbits treated with NT-1 tape.

Treatment methods for extravasations of chemotherapeutic agents: a comparative study

A rat model was used to compare early surgical intervention with injectable and topical antidotes with regard to their effectiveness in preventing cutaneous ulcers that were caused by intradermal injections of vesicant chemotherapeutic agents. The (animals) rats received bilateral flank injections of doxorubicin, vincristine, actinomycin D, mitomycin C, or carmustine (BCNU) in concentrations that were comparable to concentrations used for human patients; after the injections they underwent debridement at various intervals or received immediate applications of selected antidotes. Many "antidotes" which were frequently used, were not effective in limiting the size of the ulcer and in producing rapid healing of ulcers that were caused by experimental vesicant extravasations. Early surgical debridement was the most effective method of decreasing vesicant ulcer size and facilitating rapid ulcer healing of all the interventions tested.

Phenotypic difference between allergic and irritant patch test reactions in man

Cellular responses in allergic and irritant contact dermatitis were analysed in situ using an immunohistochemical double staining technique with the aim of uncovering phenotypical differences of diagnostic importance. Allergic and irritant patch test reactions were elicited in 9 individuals using the Finn chamber technique. Thirty-nine skin biopsies from these reactions and from petrolatum controls were obtained 4 to 20 days after the test applications. Cell infiltrates were present throughout the observation period in both allergic and irritant reactions, but were usually greater in the former. In both types of reaction, anti-Leu 3a reactive cells predominated over anti-Leu 2a reactive cells. HLA-DR expression on keratinocytes was found in 9 of 14 allergic reactions, but not in irritant reactions or control areas. HLA-DQ antigens were not detected on keratinocytes. The presence of HLA-DR antigens on keratinocytes may reflect an immunological response of the allergic reactions, and thus be of diagnostic relevance.

Industrial airborne irritant or allergic contact dermatitis

Industrial airborne irritant or allergic contact dermatitis is commonly observed in many factories. Examples of airborne irritants include fibres (such as fibreglass or rockwool), various kinds of dust particles (such as cement, slag, sludge, insulating foam, wood chips), acids and alkalis, gasses and vapours. Airborne contact allergens are unequivocally numerous. The clinical symptoms of both irritant and allergic airborne contact dermatitis are reviewed.

Lack of experimental vesicant activity for the anticancer agents cisplatin, melphalan, and mitoxantrone

Cisplatin and L-PAM are DNA-crosslinking anticancer agents which have not been systematically studied for vesicant potential. Mitoxantrone is a new active anthracene-based, DNA intercalator which is undergoing widespread clinical testing for antitumor efficacy in man. These three agents were tested for vesicant activity in dehaired BALB/c mice given ID injections equivalent to human clinical doses. Neither cisplatin (up to 150 mg/m2) nor L-PAM (up to 71 mg/m2) produced any skin necrosis in the mice. The L-PAM solvent (acid/alcohol in propylene glycol) was ulcerogenic if injected undiluted. Mitoxantrone (up to 14 mg/m2) was not ulcerogenic in the mice, although the skin site retained a blue drug discoloration for several weeks. It is concluded that in clinically relevant doses, cisplatin, L-PAM, and mitoxantrone are not vesicants.

Odor thresholds and irritation levels of several chemical substances: a review

A collation of odor threshold data for approximately 450 chemical substances is presented. The range of odor thresholds reported in the literature is shown along with any reported threshold of irritation to humans. These data can assist the industrial hygienist in determining when an "odor" may be in excess of the Threshold Limit Value, when an organic vapor respirator is not acceptable due to the lack of an odor warning at the end of a cartridge life, and where odors may not indicate a hazard due to extremely low odor thresholds which may be well below the respective TLVs.

QSAR for upper-respiratory tract irritation

A recent paper by Muller and Greff (Fd. Chem. Toxicol., 22 (1984) 661) presents QSAR equations for upper respiratory tract irritation by compounds falling into various chemical families. In the present paper the relationships are analysed further. It is found that a general QSAR equation, covering a diverse range of structures, correlates the biological activity reported by Muller and Greff with a single physicochemical parameter, TB'. The parameter TB' is the boiling point at atmospheric pressure (TB), adjusted for compounds with Trouton constants different from 22 cal deg-1 mol-1: TB' = (Tr X TB/22) + 40(1 - Tr/22) where Tr is the Trouton constant. Some of the compounds studied were found to be more irritant than predicted by the general equation: their enhanced activity can be rationalised in terms of their chemical reactivity as electrophiles, their metabolism to electrophiles, or their hydrolysis to more irritant products.

Acute local irritative effect of (2''R)-4'-O-tetrahydropyranyladriamycin, a new antitumor antibiotic

(2"R)-4'-O-Tetrahydropyranyladriamycin hydrochloride (THP), a new antitumor antibiotic, was administered to rabbits at a concentration from 0.02 to 0.5% by instillation, or by intracutaneous, subcutaneous or intramuscular injection to study its local irritative effect. The irritative effect of THP increased with concentration. At a concentration of 0.5%, THP was irritant to the eye, skin and muscle but at a concentration of 0.1% practically no effect was observed. The effect was equal to or lower than that of doxorubicin. An instillation of 0.5% THP caused reversible irritation effect on the eye. Slight conjunctival responses (redness and chemoisis) were observed. Rinsing reduced the irritative effect. Intracutaneous injection of 0.1 ml of 0.5% THP caused well defined, moderate erythema, surface ulceration and dermal necrosis. Cutaneous muscle necrosis also occurred. At a concentration of 0.02%, dermal necrosis and inflammatory cell infiltration were observed. Erythema, as well as muscle necrosis and calcification with giant cell reaction and inflammatory cell infiltration were observed by an intramuscular injection at a concentration of 0.5%. Subcutaneous injection of 0.5% THP showed no irritative effect.

Sensory and pulmonary irritation with exposure to methyl isocyanate

Methyl isocyanate (MIC) was tested for its potency as a sensory irritant and as a pulmonary irritant in mice. To evaluate sensory irritation, animals were exposed to MIC at concentrations between 0.5 and 7.6 ppm for a period of 90 min. A characteristic reflex decrease in respiratory rate indicating sensory irritation was observed. The concentration evoking a 50% decrease in respiratory rate (RD50) was found to be 1.3 ppm. To evaluate pulmonary irritation, animals were first anesthetized and fitted with a tracheal cannula. Following recovery from anesthesia, they were exposed to MIC at concentrations between 0.4 and 7.3 ppm for a period of 90 min. A characteristic decrease in respiratory rate indicating pulmonary irritation in tracheally cannulated (TC) mice was observed. The concentration evoking a 50% decrease in respiratory rate (RD50TC) was found to be 1.9 ppm. Thus, MIC was found to be a potent sensory and pulmonary irritant.

Pain on injection and muscle irritation: a comparison of animal models for assessing parenteral antibiotics

Pain on injection due to parenteral administration of cephaloridine, cephalothin, and cefoxitin with or without 1% lidocaine was examined in a rat paw-lick model and the results compared with those obtained in a rabbit intramuscular model of irritation. In both animal models, cephaloridine caused similar or a slightly greater response than sterile water. Conversely, cefoxitin and cephalothin caused a much greater reaction than water in both models. The only major difference in the rankings by the two models was with formulations in which an anesthetic agent was incorporated into the diluent. As expected, the presence of a local anesthetic masked pain on injection but not muscle damage. The rat paw-lick model is an alternative to the traditional rabbit muscle irritation model for rapidly assessing both pain on injection and muscle irritation of parenteral formulations.

Ceftriaxone pharmacokinetics following multiple intramuscular dosing

The steady-state pharmacokinetics and tolerance of ceftriaxone after multiple i.m. doses of 0.5 and 1 g q12 h for 3.5 days were investigated in 12 healthy, adult volunteers. Ceftriaxone was rapidly absorbed after i.m. administration with mean peak times ranging from 1.3 to 1.9 h. Steady-state plasma concentrations were apparent after the third dose of both dosage regimens, with trough plasma concentrations of 24 +/- 6 and 39 +/- 8 micrograms/ml (mean +/- SD) after the 0.5 and 1 g q12 h regimens, respectively. Multiple i.m. administrations of ceftriaxone did not alter its elimination half-life; however, small increases were observed in the plasma clearance and volume of distribution at the 1-g regimen. These increases were attributed to the non-linear binding of ceftriaxone to human plasma proteins, and are therapeutically unimportant. Ceftriaxone was well tolerated and serious or lasting adverse reactions were not encountered in the study.

Immunogenicity, immunological cross reactivity and non-specific irritant properties of the exudate gums, arabic, karaya and tragacanth

An animal model has been used to investigate the immunogenicity and non-specific irritant properties of exudate gums. The materials studied were four preparations of gum arabic (Acacia spp.), two of gum karaya (Sterculia spp.), two of gum tragacanth (Astralagus spp.) and a residue obtained after ethanol extraction of gum arabic. Groups of animals were intradermally immunized with the gum in complete Freund's adjuvant. Serum antibody levels were measured by an ELISA technique and delayed hypersensitivity responses by a footpad swelling test. Antigenic cross-reactivity within each gum species was tested in a crossover fashion. All gum preparations elicited systemic immune responses after immunization. Further processing reduced immunogenicity, although there was no evidence that systemic immunity to these complex polysaccharide antigens responses could be completely abolished by processing or purification. The ethanolic extract, and some of the gum preparations, particularly tragacanth and karaya, caused considerable footpad swelling when injected intradermally. It is concluded that processing and awareness of subspecies differences can reduce the inherent immunogenicity and potential irritant effects of exudate gums.