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At least 145 records · Page 8Linked to original sources
PubMed2005

Removing low ppb level perchlorate, RDX, and HMX from groundwater with cetyltrimethylammonium chloride (CTAC) pre-loaded activated carbon.

Perchlorate contaminates vast amounts of groundwater throughout the United States which could potentially be used as potable water. Activated carbon pre-loaded with cetyltrimethylammonium chloride has been shown in this research to be an effective adsorbent for removing perchlorate from three low conductivity (50-66 microS/cm) groundwaters containing perchlorate (ClO(4)(-)) concentrations of 0.85, 1.0, and 5.6 parts per billion (ppb), respectively. In rapid small-scale column tests (RSSCTs), the virgin granular activated carbon (GAC) (used as a control) treated between 20,000 and 40,000 bed volumes (BV) of water. In contrast, the activated carbon that was pre-loaded with CTAC processed 170,000-270,000 BV before perchlorate was detected above 0.25 ppb in the effluent. Though this pre-loading significantly increased the capacity for perchlorate, it also diminished the GAC's capacity to remove organics. The groundwater containing 1 ppb ClO(4)(-) also contained the nitro-organics HMX (0.6 ppb) and RDX (5.5-6.6 ppb). RDX was detected in the effluent from the CTAC-pre-loaded bed after only 8000 BV had been processed whereas 308,000 BV could be processed through the virgin bed before RDX was detected. Likewise, HMX breakthrough was observed after 116,000 BV in the CTAC-pre-loaded bed while the virgin RSSCT exhibited no breakthrough of HMX during a test that was operated for 309,000 BV. However, by combining a CTAC-pre-loaded bed followed by a virgin GAC bed in series, both perchlorate and RDX could be removed for the same length of time.

Adsorption↗
PubMed2004

Reference dose for perchlorate based on thyroid hormone change in pregnant women as the critical effect.

The most relevant data for developing a reference dose (RfD) for perchlorate exposures comes from human epidemiology and clinical studies, supplemented with available and extensive information on experimental animals. Specifically, serum T4 decrease is the critical effect of perchlorate, based on a mode-of-action analysis and the evidence provided by the body of rodent studies on perchlorate. However, no T4 decreases have been observed in human populations following perchlorate exposure at non-therapeutic doses. An RfD of 0.002 mg/kg-day can be derived using an epidemiology study. A freestanding NOAEL of 0.006 mg/kg-day for T4 decrease was identified in children from the epidemiology study. The use of this NOAEL has the advantage of a being identified in a sensitive subgroup, neonates and children. Data are sufficient to estimate an overall uncertainty factor of 3-fold with this NOAEL based on expected differences in toxicokinetics and toxicodynamics between children, and pregnant women and their fetuses, the second identified sensitive subgroup for perchlorate, and concerns about the over-iodination of this population. This RfD is supported by a human clinical study using inhibition of iodine uptake in adults as a measurable surrogate for the critical effect of T4 decrease in humans. However, although this latter study has a well-established dose-response curve for inhibition of iodine uptake, even perchlorate doses that result in a 70% inhibition of iodine uptake have no apparent effect on human T4 levels. Thus, the use of this study as the primary basis of the RfD is problematic. Nevertheless, a benchmark dose of 0.01 mg/kg-day was identified in this clinical study, which supports a threshold value of 0.006 mg/kg-day identified by its authors and the RfD of 0.002 mg/kg-day estimated in this paper.

Administration, Oral↗
PubMed2001

Biological perchlorate reduction in high-salinity solutions.

Perchlorate (ClO4-) has been detected in numerous ground and surface waters, and has recently been added to the drinking water Candidate Contaminant List in the United States. Perchlorate can be removed from drinking water using ion exchange, but this results in the production of highly saline (7-12%) perchlorate-contaminated brines. Perchlorate-degrading microbial enrichments capable of growth in highly saline water were obtained by screening six salt water environments including marine and lake surface waters, salt marshes, subtidal sediments, and a biofilm/sludge from a seawater filter. Perchlorate reduction was obtained in three of these samples (seawater, saline lake water, and biofilm/sludge) at a salinity of 3%. The salinity range of two of these cultures was extended through serial transfers into media having higher salt concentrations (3-7%). Growth rates were measured over a salinity range of 1-15%. The maximum growth rate measured for the saline lake-water enrichment was 0.060+/-0.003 d(-1) (doubling time of 11.6+/-0.8 d) at a salinity of 5%. Growth rates decreased to 0.037+/-0.002 d(-1) at a salinity of 11%, and no growth was observed at salinities of 13 or 15%. These results demonstrate for the first time that biological perchlorate reduction is possible in solutions having a salinity typical of ion exchange brines.

Biodegradation, Environmental↗
PubMed2003

Sensitive high-performance liquid chromatography method for the determination of low levels of perchlorate in biological samples.

A rapid and sensitive high-performance liquid chromatography (HPLC) method was developed to detect perchlorate in tissues of male and female rats, both pregnant and lactating (including milk) after administration of perchlorate. Supernatants of ethanol precipitated rat fluids and tissues were evaporated to dryness under nitrogen and reconstituted in deionized water. Reconstituted samples were injected into HPLC system coupled with conductivity detection. Isocratic separation of perchlorate was achieved using an anion-exchange column with sodium hydroxide as mobile phase and a conductivity detector. In this method, perchlorate showed a linear response range from 5 to 100 ng/ml. The lower detection limits for perchlorate in fluids and tissues of rats were 3-6 ng/ml and 0.007-0.7 mg/kg, respectively. The described method has the unique advantage over the existing methods of determining low traces of perchlorate in different biological matrices without complex sample preparation.

Animals↗
PubMed2005

Analysis of perchlorate in human urine using ion chromatography and electrospray tandem mass spectrometry.

Because of health concerns surrounding widespread exposure to perchlorate, we developed a sensitive and selective method for quantifying perchlorate in human urine using ion chromatography coupled with electrospray ionization tandem mass spectrometry. Perchlorate was quantified using a stable isotope-labeled internal standard ((18)O(4)-perchlorate) with excellent assay precision (coefficient of variation <5% for repetitively analyzed quality control material). Analytical accuracy was established by blind analysis of certified proficiency testing materials prepared in synthetic urine matrix; calculated amounts deviated minimally from true amounts, with percent differences ranging from 2% to 5%. Selective chromatography and tandem mass spectrometry reduced the need for sample cleanup, resulting in a rugged and rapid method capable of routinely analyzing 75 samples/day. The lowest reportable level (0.025 ng/mL) was sufficiently sensitive to detect perchlorate in all human urine samples evaluated to date, with a linear response range from 0.025 to 100 ng/mL. This selective, sensitive, and rapid method will help elucidate any potential associations between human exposure to low levels of perchlorate and adverse health effects.

Adult↗
PubMed2004

Determination of perchlorate anion in foods by ion chromatography-tandem mass spectrometry.

A rapid, sensitive, and specific method was developed for determining perchlorate anion in lettuce, cantaloupe, bottled water, and milk. A test portion of chopped crop homogenate was extracted with diluted nitric acid and filtered. Milk proteins were precipitated with acetonitrile, and the supernatant, after centrifugation, was cleaned up on a graphitized carbon solid-phase extraction column. Water samples were analyzed directly. All test solutions were syringe filtered and mixed with an 18O4-labeled perchlorate internal standard before ion chromatography-tandem mass spectrometry. A strong anion exchange column eluted with 100 mM ammonium acetate in 50:50 (v/v) acetonitrile/water was interfaced via electrospray ionization to a triple stage quadrupole mass spectrometer operated in the negative ion mode. The labeled internal standard corrected for any sample matrix effects on measured signals. Four parent-to-product ion transitions, for loss of oxygen, were monitored for native and 18O4-labeled perchlorate anion, respectively: 35Cl-perchlorate, m/z 99 --> 83 and 107 --> 89; 37Cl-perchlorate, m/z 101 --> 85 and 109 --> 91. The limit of quantitation was 1.0 microg/kg in lettuce, 2.0 microg/kg in cantaloupe, 0.50 microg/L in bottled water, and 3.0 microg/L in milk. Native perchlorate was recovered from fortified test portions in the range 93-107% for lettuce, 107-114% for cantaloupe, 100-115% for bottled water, and 99-101% for milk.

Animals↗
PubMed2003

Chlorine isotope fractionation during microbial reduction of perchlorate.

Perchlorate contamination of surface water and groundwater is an emerging public health problem that has adversely affected the drinking water supplies of millions of people in the western United States. Microbial reduction has shown promise as a cost-effective means for in situ bioremediation of perchlorate-contaminated water. Measurements of stable isotope ratios of light elements (H, C, N, O, S, Cl) can often be used to distinguish biodegradation of organic and inorganic molecules from abiotic loss mechanisms such as adsorption, dispersion, or volatilization because of the relatively large kinetic isotope effects accompanying biodegradation. We quantified chlorine isotope fractionation during perchlorate biodegradation by a common perchlorate-reducing bacterium, Dechlorosoma suillum, initially isolated from a perchlorate-contaminated groundwater source in southern California. The values of the chlorine isotopic fractionation factor alpha derived from two microcosm experiments were alpha = 0.9834 +/- 0.0001 (R2 = 0.9999) and alpha = 0.9871 +/- 0.0008 (R2 = 0.9832). These alpha values indicate that the rate of the 35ClO4 reduction is approximately 1.3-1.7% faster than that of the 37ClO4 reduction. This relatively large kinetic isotope effect indicates that chlorine isotope analysis provides a sensitive technique by which to document in situ bioremediation of perchlorate in groundwater.

Chlorine↗
PubMed2005

Numerical model for biological fluidized-bed reactor treatment of perchlorate contaminated groundwater.

Biological fluidized-bed reactor (BFBR) treatment with 1.3 mm granular activated carbon as support medium is being used for removal of 2.6 mg/L perchlorate from contaminated groundwater in California. The California drinking-water action level of 4 microg/L for perchlorate requires 99.9% perchlorate removal. Sufficient ethanol, the electron donor, is added to remove oxygen and nitrate as well as perchlorate, as all three serve as electron acceptors, but with biological preference for oxygen and nitrate. A numerical BFBR model based upon basic physical, chemical, and biological processes including reaction stoichiometry, biofilm kinetics, and sequential electron acceptor usage was developed and evaluated with the full-scale treatment results. A key fitting parameter was bacterial detachment rate, which impacts reaction stoichiometry. For best model fit this was found to vary between 0.062 and 0.31 d(-1), with an average of 0.22 d(-1). The model indicates that GAC particle size, reactor diameter, and perchlorate concentration affect BFBR performance. While empty-bed detention time might be decreased somewhat below 10 min by an increase in either GAC particle size or reactor diameter, the current design provides a good factor of safety in operation. With a 10 min detention time, the effluent goal of 4 microg/L should be achievable even with influent perchlorate concentration as high as 10 mg/L.

Adsorption↗
PubMed2006

Uptake of N-nitrosodimethylamine (NDMA) from water by phreatophytes in the absence and presence of perchlorate as a co-contaminant.

The uptake and fate of the emerging contaminants N-nitrosodimethylamine (NDMA) and perchlorate in phreatophytes was studied in a hydroponics system under greenhouse conditions. NDMA is a potent carcinogen, and perchlorate disrupts the functioning ofthe human thyroid gland. The rate of removal of NDMA from solution by rooted cuttings of black willow (Salix nigra) and hybrid poplar (Populus deltoides x nigra, DN34) trees varied seasonally, with faster removal in summer months when transpiration rates were highest. A linear correlation between the volume of water transpired and mass of NDMA removed from the root zone was observed, especially at higher NDMA concentrations. In bioreactors dosed with both NDMA (0.7-1.0 mg L(-1)) and perchlorate (27 mg L(-1)), no competitive uptake of NDMA and perchlorate was observed. While NDMA was primarily removed from solution by plant uptake, perchlorate was predominantly removed by rhizodegradation. In the presence of NDMA, a slower rate of rhizodegradation of perchlorate was observed, but still significantly faster than the rate of NDMA uptake. For experiments conducted with radiolabeled NDMA, 46.4 +/- 1.1% of the total 14C-activity was recovered in the plant tissues and 47.5% was phytovolatilized. The 46.4 +/- 1.1% recovered in the plants was distributed as follows: 18.8 +/- 1.4% in leaves, 15.9 +/- 5.9% in stems, 7.6 +/- 3.2% in branches, and 3.5 +/- 3.3% in roots. The poor extractability of NDMA with methanol-water (1:1 v/v) from stem and leaf tissues suggested that some fraction of NDMA was assimilated. The calculated transpiration stream concentration factor (TSCF) of 0.28 +/- 0.06 suggests that NDMA is passively taken up by phreatophytes, and mainly phytovolatilized.

Biodegradation, Environmental↗
PubMed2005

Accumulation and perchlorate exposure potential of lettuce produced in the Lower Colorado River region.

The Colorado River is contaminated with perchlorate concentrations of 1.5-8 microg/L, an anion linked to thyroid dysfunction. Over 90% of the lettuce (Lactuca sativa L.) consumed during the winter months in the United States is produced in the Lower Colorado River region. Studies were conducted in this region to survey the potential for lettuce perchlorate accumulation and estimate potential human exposure to perchlorate from lettuce. Total uptake of perchlorate in the above-ground plant of iceberg lettuce was approximately 5 g/ha. Exposure estimates ranged from 0.45 to 1.8 microg/day depending on lettuce types and trimming. For all lettuce types, hypothetical exposures were less than 4% of the reference dose recommended by the National Academy of Sciences. Results show the relative iodide uptake inhibition potential because of lettuce nitrate was 2 orders of magnitude greater than that associated with the corresponding trace levels of perchlorate. These data support the conclusion that potential perchlorate exposures from lettuce irrigated with Colorado River water are negligible relative to acute or long-term harmful amounts.

Arizona↗
PubMed1978

Extraction of CEA from tumour tissue, foetal colon and patients' sera, and the effect of perchloric acid.

The use of perchloric acid and water for the extraction of CEA from tumour and foetal tissues has been investigated. In the case of tumour, lower recoveries of CEA were obtained from perchloric acid extracts than from aqueous extracts of the same tissue. CEA has also been extracted with 3M KCl solution from insoluble perchloric acid residues of tumour homogenates and cancer patients' serum. Whilst a large proportion of CEA activity recovered from tumour was associated with the perchloric acid residue, the corresponding amounts from serum were very small. CEA elution volumes for each extract, obtained by assay of Sephadex G-200 column fractions, showed significant heterogeneity in molecular size. The purified CEA pools also showed quantitative variations in the binding profiles on Con A-Sepharose. It has been shown that perchloric acid modifies the carbohydrate in CEA, thus altering its Con A-binding properties. Preliminary experiments with foetal colon have demonstrated that, unlike colorectal CEA, a significant proportion of foetal CEA was not bound to ConA. Comparative immunodiffusion showed immunological identity of CEA from the various extracts, although the purified aqueous extract produced an additional precipitin reaction, indicating a second antigen which is relatively unstable or less soluble in perchloric acid.

Bronchial Neoplasms↗
PubMed1996

Perchlorate differentially potentiates excitation-contraction coupling of diaphragm muscle from mdx and control mice.

The effects of perchlorate (6-40 mM) on contractile properties and depolarization-contraction coupling of diaphragm have been tested in muscle fibre bundles from 8 to 12-week-old mdx and control mice. Twitch contractile properties were affected by perchlorate to a similar extent in mdx and control muscles. In the absence of perchlorate, voltage-dependent parameters of both activation and inactivation were similar in mdx and control muscles. In both mdx and control muscles, perchlorate induced a shift of activation and inactivation curves toward more negative potentials. However, mdx diaphragm fibres were less sensitive to perchlorate in the low range of concentrations (6-12 mM). These results are unlikely to be due to a possible effect of the lack of dystrophin on the excitation-contraction coupling voltage sensor or ryanodine receptor. However, necrosis and regeneration occur in mdx mouse diaphragm and it is postulated that the presence of a high proportion of not fully mature fibres could contribute to the reduced sensitivity of mdx diaphragm fibres to perchlorate.

Animals↗
PubMed2000

A 90-day drinking water toxicity study in rats of the environmental contaminant ammonium perchlorate.

Perchlorate (ClO(4)(-)), the dissociated anion of perchlorate salts such as ammonium, potassium, and sodium perchlorate, has been recently recognized as a persistent and pervasive contaminant of drinking water supplies in a number of metropolitan areas. Perchlorate is of concern because of uncertainties in the toxicological database available to address the potential human health effects of low-level exposure. The purpose of this study was to evaluate the subchronic toxicity of perchlorate when administered to Sprague-Dawley rats as ammonium perchlorate (AP) for 14 or 90 days. The study consisted of an untreated control group and five treatment groups that received continuous exposure to AP via the drinking water at dosage levels of 0.01, 0.05, 0.2, 1.0, and 10.0 mg/kg/day. The study design included a nontreatment recovery period of 30 days to evaluate the reversibility of any AP-induced effects at the 0.05, 1.0, and 10.0 mg/kg/day levels. The study also investigated the potential effects of AP on male sperm parameters, female estrous cyclicity, bone marrow micronucleus formation, and serum hormone levels, i.e., triiodothyronine (T(3)), thyroxine (T(4)), and thyroid stimulating hormone (TSH). No toxicologically meaningful differences were observed between the control and AP-treated groups with respect to survival, clinical observations, body weights, food consumption, water consumption, ophthalmology, hematology, clinical chemistry, estrous cycling, sperm parameters, or bone marrow micronucleus formation. A target organ effect was produced by AP in the thyroids of male and female rats at the 10 mg/kg/day level after 14 and 90 days of exposure. The effect was characterized by significantly increased thyroid weights and thyroid histopathology consisting primarily of follicular cell hypertrophy with microfollicle formation and colloid depletion. These changes were reversible after a nontreatment recovery period of 30 days. Statistically significant changes in TSH and thyroid hormones were observed at all AP dosage levels tested; however, no thyroid organ weight or histopathological effects were observed at AP dosage levels < or = 1.0 mg/kg/day. In the absence of thyroid organ weight and histopathological effects, the toxicological significance of TSH and thyroid hormone changes at AP dosage levels < or = 1.0 mg/kg/day remains to be determined.

Animals↗
PubMed2007

Effects of prolonged exposure to perchlorate on thyroid and reproductive function in zebrafish.

The objectives of this study were to determine the effects of prolonged exposure to perchlorate on (1) thyroid status and reproductive performance of adult zebrafish (Danio rerio) and (2) F1 embryo survival and early larval development. Using a static-renewal procedure, mixed sex populations of adult zebrafish were exposed to 0, 10, and 100 mg/l nominal concentrations of waterborne perchlorate for 10 weeks. Thyroid histology was qualitatively assessed, and females and males were separated and further exposed to their respective treatments for six additional weeks. Eight females in each tank replicate (n = 3) were paired weekly with four males from the same respective treatment, and packed-egg (spawn) volume (PEV) was measured each of the last five weeks. At least once during weeks 14-16 of exposure, other end points measured included fertilization rate, fertilized egg diameter, hatching rate, standard length, and craniofacial development of 4-day-postfertilization larvae and thyroid hormone content of 3.5-h embryos and of exposed mothers. At 10 weeks of exposure, perchlorate at both concentrations caused thyroidal hypertrophy and colloid depletion. A marked reduction in PEV was observed toward the end of the 6-week spawning period, but fertilization and embryo hatching rates were unaffected. Fertilized egg diameter and larval length were increased by parental exposure to perchlorate. Larval head depth was unaffected but the forward protrusion of the lower jaw-associated cartilage complexes, Meckel's and ceratohyal, was decreased. Exposure to both concentrations of perchlorate inhibited whole-body thyroxine content in mothers and embryos, but triiodothyronine content was unchanged. In conclusion, prolonged exposure of adult zebrafish to perchlorate not only disrupts their thyroid endocrine system but also impairs reproduction and influences early F1 development.

Analysis of Variance↗
PubMed1988

Structure of barium perchlorate trihydrate.

Ba(ClO4)2.3H2O, Mr = 390.28, hexagonal, P63/m, a = 7.277 (2), c = 9.656 (1) A, V = 442.9 (1) A3, Z = 2, F(000) = 368, D chi = 2.93 g cm3, lambda(Mo K alpha) = 0.71069 A, T = 295 K, mu = 52.60 cm1, 456 unique reflections, R = 0.023. The barium atoms in this structure are coordinated by six water oxygens, O(3), at 2.919 (1) A and by six perchlorate oxygens, O(2), at 3.026 (2) A in a slightly distorted icosahedral arrangement, the average Ba-O separation thus being approximately 2.97 A. The perchlorate ion just fails to have regular tetrahedral geometry within the experimental error, and has an average Cl-O bond length of 1.433 (6) A. Consistent with hydrogen bonding delineated on the basis of least-squares-refined hydrogen-atom positions, each axial [O(1)] perchlorate oxygen is hydrogen bonded to three water molecules and each trigonal [O(2)] perchlorate oxygen is hydrogen bonded to two water molecules; thus each perchlorate ion is hydrogen bonded to nine water molecules. Conversely, each water molecule [O(3)] oxygen is hydrogen bonded to six perchlorate ions to two through axial [O(1)] oxygens and to four through trigonal [O(2)] oxygens.

Barium↗
PubMed1989

Structure of copper(II) perchlorate hexahydrate.

Cu(ClO4)2.6H2O, Mr = 370.54, monoclinic, P2(1)/c, a = 5.137 (1), b = 22.991 (3), c = 13.849 (2) A, beta = 90.66 (1) degree, V = 1635.4 (4) A3, Z = 6, Dx = 2.26 g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 26.44 cm-1, T = 296 K, F(000) = 1122, 2911 unique reflections having I greater than sigma 1, R = 0.030. Each of the two inequivalent copper ions is coordinated by six water-molecule O atoms in a significantly distorted octahedral arrangement. Each of the three inequivalent but geometrically quite similar perchlorate groups is slightly distorted from regular tetrahedral geometry. The overall observed mean Cl-O distance is 1.429 (5) A while the overall observed mean perchlorate O-O distance is 2.333 (8) A. Both the Cu-O complexes and the perchlorate ions were tested and found to behave as rigid bodies. The perchlorate-ion parameters corrected for rigid-body motion are: overall mean Cl-O distance, 1.453 (6) A; overall mean perchlorate O-O distance, 2.372 (8) A. Location and refinement of the 18 H atoms gave a detailed account of hydrogen bonding, which occurs between oxygen octahedra, between oxygen octahedra and perchlorate groups, and, more weakly, within oxygen octahedra.

Chemical Phenomena↗
PubMed1987

Perchlorate and the relationship between charge movement and contractile activation in frog skeletal muscle fibres.

1. The effects of perchlorate ions (1-8 mM) on intramembrane charge movement, myoplasmic Antipyrylazo III Ca2+ transients and contractile activation were examined in voltage-clamped cut skeletal muscle fibres of the frog. 2. Perchlorate shifted both the voltage dependence of charge movement and the rheobase of the strength-duration relation for contraction threshold towards more negative membrane potentials. 3. Both charge movements and myoplasmic Ca2+ transients were much slower at the new rheobase in the presence of perchlorate than in the control solution but there was no change in the threshold amount of charge or in the calculated peak binding of Ca2+ to troponin C. 4. The peak release rate had a steeper voltage dependence than the non-linear charge, but a lower concentration (2 mM) of perchlorate shifted both voltage dependences equally without altering the maxima in the amount of charge and in the rate of Ca2+ release. 5. The voltage dependence of the difference between total charge and charge at the threshold of Ca2+ transients agreed well with the voltage dependence of the rate of Ca2+ release in both the presence and absence of perchlorate. 6. It is concluded that the effect of perchlorate on contractile activation can be accounted for by its action on the intramembrane charge movement responsible for contraction, without significant effects on subsequent Ca2+ release from the sarcoplasmic reticulum or on Ca2+ binding to regulatory sites of troponin C.

Action Potentials↗
PubMed1992

Effects of perchlorate on excitation-contraction coupling in frog and crayfish skeletal muscle.

1. The effects of perchlorate on various aspects of excitation-contraction coupling in frog and crayfish skeletal muscle have been examined in optical and electrophysiological experiments on voltage-clamped cut muscle fibres. 2. In the frog, perchlorate shifted the voltage dependence of charge movement and consequent sarcoplasmic reticulum (SR) Ca2+ release, but it had little effect on the slow inward calcium current. 3. In the crayfish, perchlorate had little effect on either calcium currents or the SR Ca2+ release that contributes to myoplasmic Ca2+ elevations. 4. Two alternative explanations for these results are discussed. There may be two functional types of dihydropyridine receptors, those (perchlorate sensitive) that communicate with the ryanodine receptor via charge movement and those (perchlorate insensitive) that function solely as Ca2+ entry points. Alternatively, the results would be consistent with two separate voltage sensors on each dihydropyridine receptor, only one of which is perchlorate sensitive.

Animals↗