Summary table of the various effects of BPA exposure on reproductive system of laboratory rodents.
Bisphenol A [4,4′‐(propane‐2,2‐diyl)diphenol] (abbreviated as BPA) is a synthetic xenoestrogenic chemical and endocrine disruptor. It is a most common plasticizer that is used widely to produce epoxy resin and polycarbonate plastics, enters the living system through food and water contamination and generates health hazards. Researches are being conducted to explore the adversity that BPA exerts in living body, and for this reason, model organisms are of scientific choice. Rodents, zebrafish, Drosophila, nematodes, crustaceans and echinoderms are being used for monitoring the effect of BPA on their life history traits, nervous system, endocrine system, reproductive systems, behaviour, etc., which could help us to anticipate what kind of challenges BPA is putting in human life. This systematic review is focused on the latest research trend on BPA toxicity on different model organisms.
- bisphenol A
- Drosophila melanogaster
- reproductive system
- life history traits
- developmental defects
- gene expression
Bisphenol A [4,4′‐(propane‐2,2‐diyl)diphenol] (abbreviated as BPA) is a synthetic xenoestrogenic chemical and endocrine disruptor [1–3] widely used in dentistry, food packaging and as lacquers to coat food cans, bottle‐tops and water pipes since the 1960s. It is a most common plasticizer that is used widely to produce epoxy resin and polycarbonate plastics. It was first synthesized by Dianin in 1891 and was investigated for potential commercial use in the 1930s during a search for synthetic estrogens. BPA enters the living system inconspicuously through various routes, particularly through food and water contamination, and creates multitude of imperilments at cellular, molecular and genetic level. The EC50 and LC50 values of BPA range from 1.0 to 10 mg/L (Environment Canada 2008), and BPA is declared as ‘moderately toxic’ and ‘toxic’ to aquatic biota by the European Commission and the United States Environmental Protection Agency (US EPA), respectively , Commission of the European Communities 1996]. Moreover, environmentally relevant concentrations (12 mg/L or lower) of BPA were also found to be harmful as far as wildlife is concerned . BPA exerts its effect through direct binding to estrogen receptor (ER) in a wide range of species that includes invertebrates, fish, amphibians, reptiles, birds and mammals . BPA binds both ERα and ERβ receptors, with approximately 10‐fold higher affinity to ERβ .
The toxicokinetics of BPA exposure reveal that after oral administration in human, BPA is metabolized rapidly in the intestine and liver. BPA is not completely metabolized via Phase I reactions, but it is rapidly conjugated with glucuronic acid (Phase II metabolism) to produce non‐active BPA‐glucuronide in the gut wall and liver. Little amount of BPA also reacts with sulphate to form BPA‐sulphate compound. The formation of BPA conjugates with other chemical moieties is a detoxification process [8, 9]. The BPA conjugates formed in the liver reach the kidney through blood circulation and then excreted in the urine with terminal half‐lives of less than 6 hours [10, 11]. According to a declaration made in 2010 by U.S. Food and Drug Administration, exposure to BPA is alarming because of possible health hazards it exerts on brain, behaviour and prostate gland of foetuses, infants and children. The European Food Safety Authority (EFSA) reviewed new scientific information on BPA in the years 2008, 2009, 2010, 2011 and 2015, concluding on each occasion the known level of exposure to BPA to be hazardous. In February 2016, France announced that it intends to propose BPA as a REACH Regulation candidate substance of very high concern (SVHC).
Owing to difficulty in doing research on human subjects, researchers prefer to use model organisms to test the toxic effect of xenobiotic agents in living system. This approach is also popular in the research on BPA as the agent is ubiquitously present in our ‘plastic wrapped world’ and no perfect control subject could be obtained in natural environment. Several model organisms from different taxa are in use for studying the effects of BPA on their life history, morphological traits, reproductive functioning, neural functioning and behaviour. The outcome of these studies helps to anticipate the probable adversity that BPA inflicts in human body. Keeping all these factors in mind, a critical review on latest research works is presented here to understand the deleterious effects of BPA exposure on different vertebrate and invertebrate model organisms that could facilitate the understanding of human health hazards due to exposure to this xenoestrogen and endocrine disruptor BPA.
2. Vertebrate model animals
2.1. Studies on rodents
Owing to close taxonomic proximity, rodents, including rat, mice and hamster, resemble most with of humans among all other commonly used vertebrate models, and many symptoms of human conditions can be replicated in mice and rats. For that reason, rodents occupy the most preferred model animal in biomedical research, and keeping pace with this global trend, BPA researchers also rely on rodents to unravel the BPA effects on mammals.
2.1.1. Effects on reproductive system
Almost all xenobiotic agents have been tested for their toxicity in rodents to anticipate the probable effects on human body owing to taxonomic closeness of rodents and human as primate. There is extensive evidence that BPA imperils development of reproductive system in male rats and mice, although there appear to be species, strain and dose differences in the sensitivity of specific outcomes to BPA . There are numerous studies of the effects of low doses of BPA on the development of the female and male reproductive organs in rats and mice. Findings include chromosomal abnormalities in oocytes in females [12, 13] and long‐term effects on accessory reproductive organs that are not observed until mid‐life, such as uterine fibroids and para‐ovarian cysts . In Newbold’s study , outbred female CD‐1 mice were treated on days 1–5 with subcutaneous injections of BPA (10, 100 or 1000 μg/kg/day). At 18 months of age, ovaries and reproductive tract tissues exhibited significant increase in cystic ovaries and cystic endometrial hyperplasia in the BPA‐treated group. Progressive proliferative lesion of the oviduct and cystic mesonephric (Wolffian) duct remnants was also seen in BPA‐treated groups .
The effect of BPA on male reproductive organs and function includes decrease in testosterone secretion  and sperm production [17, 18]. Impacts on other reproductive structures include reduction in the size of the epididymis at a dose of 2 ng/g and enlargement of the size of prostate ducts in the male foetuses when pregnant females were exposed to a dose of 10 μg/kg BPA/day [19, 20]. These findings are consistent with effects of low doses of positive control chemicals, such as diethylstilbestrol (DES) and ethinyl estradiol. Moreover, the testicular function impairment includes germ cell sloughing, disruption of the blood‐testis‐barrier and germ cell apoptosis [21, 22].
Impairment in testicular function is also evident in other studies [23, 24, 25]. The effects of BPA resemble more or less the estrogenic effects on the testes [18, 26, 27] with reduction in daily sperm production , deformed acrosomal vesicles, acrosomal caps, acrosomes and nuclei of the spermatids. Tohei et al.  reported that plasma concentration of testosterone was decreased, and LH was increased in rats after administration of BPA. Testicular content of inhibin was decreased. The testicular response to human chorionic gonadotropin (hCG) for progesterone and testosterone release was also decreased in BPA‐treated rats. These results suggest that BPA directly inhibits testicular functions by disrupting the pathway of negative feedback regulation.
Studies have revealed that BPA exposure also affects the female systems, and it is found to be associated with a number of anomalies like polycystic ovarian syndrome , endometriosis  and anovulation. Studies have also been conducted to evaluate effects of BPA on development of mammary gland.
|Affected area||Model; time and route of exposure||Effect||Citation|
|Ovary||Mice; developmental, pellet implantation||Disruption of early oogenesis||Susiarjo et al. |
|Ovaries and reproductive tract tissues||CD‐1 mice; developmental, injection||Increase in cystic ovaries and cystic endometrial hyperplasia||Newbold et al. |
|Mammary gland||Mice, Rats; developmental, injection, minipump||Enhanced growth and differentiation||Markey et al. ; Munoz‐de‐Toro et al. ; Soto et al. ; Durando et al. ; Murray et al. |
|Testes||Mice, rats ; developmental, adult, oral, injection||Decreased testosterone secretion and sperm production ; deformed sperm with reduced motility||Akingbemi et al. ; Aikawa et al. ; Toyama et al. ; Al‐Hiyasat et al. ; Chitra et al. ; Sakaue et al. |
|Seminiferous tubules||C57BL/6 mice; adult, oral||Disrupted||Takao et al. |
|Blood||Rats, adult, oral||↓ Plasma testosterone and ↑ LH||Tohei et al. |
|Prostate gland||CF‐1 mice, CD‐1 mice; developmental, oral||↑ weight, ↑ prostate duct volume||Thayer et al. ; Timms et al. |
|Epididymis||CF‐1 mice; developmental, oral||↓ size||vom Saal et al. |
2.1.2. Effects on nervous system
BPA has both indirect and direct effects on the nervous system. Since gonadal hormones in conjunction with other neurotrophins regulate cell death, neuronal migration, neurogenesis and neurotransmitter plasticity , BPA, in disrupting sex hormone functions, can affect brain development. Estrogen plays a major role in development and differentiation of certain parts of male and female brains. Male and female brains are exposed to different amounts of estrogen during development, and this appears to shape some regions of the brain differently. One of these regions is the hypothalamus, which controls a variety of basic functions including hunger, mood and sex drive. Due to its estrogenic and antiandrogenic activities, BPA can interfere with the dimorphic development of the neuronal networks of male and female brain regulating  the activation of hypothalamic estrogen or androgen receptors, testosterone‐activating enzymes and hippocampal aromatase expression .
As BPA disrupts thyroid function, it can also affect the development of the nervous system because thyroid hormones regulate prenatal and neonatal development of the brain . Juvenile hypothyroidism due to BPA exposure leads to diminutive dentritic growth in hippocampal neurons of rat brain, resulting in cognitive defects including impaired memory, defective perception and attention problems . In a prenatal study  of brain development in mice treated with BPA in a dose 20 μg/kg, body revealed decrease in growth in the ventricular zone of the BPA‐treated offspring, whereas in the cortical plate, growth was increased. In addition, the expression of thyroid Receptor gene TRα (and other genes) was significantly upregulated in the cortical area of the BPA‐treated group. BPA induces cortical plate growth via upregulation of the thyroid pathway. In doing so, BPA might have disrupted normal neocortical development by accelerating neuronal differentiation and migration. BPA exposure may also interfere with the development and expression of normal sex differences in cognitive function, via inhibition of estrogen‐dependent hippocampal synapse formation in female rat  and testosterone‐induced hippocampal synapse formation in male mice .
In addition, BPA may directly cause neurodegeneration. BPA enhances hydroxyl radical formation in the rat brain , and it is induced by 1‐methyl‐4‐phenylpyridinium ion (MPP+) . This leads to neurodegeneration of the
|Affected area||Model; time and route of exposure||Effect||Citation|
|Brain||Mice; developmental, injection||↓ growth of ventricular zone,||Nakamura et al. |
|↑ cortical plate growth|
|Hypothalamus||Mice, rats; developmental, injection||Affect sex differences in brain development||Negri‐Cesi |
|Hippocampus||Sprague‐Dawley rats; adult, injection||Inhibits synapse formation at CA1 area||MacLusky et al. ; Leranth et al. |
|Striatum||Rat; adult, infusion||Neurodegeneration of ||Obata and Kubota |
2.1.3. Effects on chromosomes
Recently, researches have unravelled the fact that maternal exposure to a very low dose (20 ng/g body weight) of BPA disrupts alignment of chromosomes during meiosis in the embryonic oocyte during formation of the primary follicles. This abnormality was also observed in mice that were housed in polycarbonate cages and that were provided water in polycarbonate bottles that had been damaged by exposure to a harsh detergent during washing . This finding suggests that exposure to BPA during the time that meiosis resumes in the mid‐cycle surge by luteinizing hormone (LH) can result in an increase in foetal aneuploidy and subsequent spontaneous abortion in humans . The effect of BPA on aneuploidy has also been examined in cell culture [48–51]. In the study by Tsutsui et al. [48, 49], treatment of Syrian hamster embryo cells with BPA (100 μM) for 48 hours resulted in statistically significant increases in the percentage of aneuploid metaphases with chromosome losses. Reports are also available that revealed delay in the meiotic cell cycle, possibly by a mechanism that degrades centrosomal proteins and thus perturbs the spindle microtubule organization and chromosome segregation in mouse oocyte during meiosis. When cultured cells were exposed to BPA during the transition from meiosis‐I to meiosis‐II, a delay in meiosis‐I had been observed. This transition phase usually lasts for 8–10 hours in mice, but for BPA‐exposed culture, 53% of cells remained in meiosis‐I. Insignificant counts of cells were found in anaphase .
2.1.4. Effects on behaviour
With inevitable effects of BPA on nervous system, behavioural patterns of rodents are reported to be affected by BPA exposure. An increase in defensive aggression was reported in the offspring of male Sprague‐Dawley rat whose mother was offered oral BPA dose (40 μg/kg/day) throughout gestation . In addition, increased aggressiveness (using a composite score of aggression) in male CD‐1 mouse offspring was evident as a result of oral administration of low dose of BPA (2 and 20 ng/g of body weight) to pregnant females on gestation days 11–17 [54, 55].
A series of studies demonstrated that prenatal and neonatal exposure to BPA upregulates activities of the dopamine system and induced hyperactivity among the experimental rat . Support to this primary report came from the study  that revealed prenatal and neonatal exposure of mice to BPA caused upregulation of dopamine D1 receptors, produced hyperlocomotion and increased rewarding responses induced by methamphetamine. Narita et al.  demonstrated that exposure of mice to BPA during either organogenesis or lactation, but not implantation and parturition, significantly enhanced the morphine‐induced hyperactivity and rewarding effects. In a rat model, Ishido et al.  demonstrated that neonatal exposure to BPA (87 nmol/10 μl/rat) caused significant hyperactivity at 4–5 weeks of age, and significantly decreased gene expression of dopamine transporter at 8 weeks.
Negishi et al.  demonstrated that BPA impaired both passive and active avoidance learning among offspring of Fisher 344 rats that were fed a low dose of BPA (0.1 mg/kg/day orally) during pregnancy and lactation. There are also evidences of depressed maternal behaviour in female exposed [61, 62]. There are also reports by Dessi-Fulgheri et al.  about decrease in play behaviour of juvenile Sprague‐Dawley rats due to exposure of BPA. Authors observed a masculinization of female behaviour in two behavioural categories, that is, play with females and sociosexual exploration, an effect probably mediated by the estrogenic activity of BPA in the central nervous system.
Foetal/neonatal exposure to low doses of BPA causes sex differences in brain structure, chemistry and behaviour. BPA interferes with the normal processes of sexual differentiation, with brain changes in both male and female rat and mice [61, 64]. Evidence of anatomical alterations in brain sexual differentiation was evident in male and female offspring born to mother exposed to 25 or 250 ng BPA/kg body weight per day . In Fujimoto’s experiment, prenatal exposure to BPA affected male rats and abolished sex differences in rearing behaviour in the open‐field test and struggling behaviour in the forced swimming test. Table 3 shows the summary of the experimental results on the behavioural aspects of laboratory rodents.
|Event||Model; time and route of exposure||Effect||Citation|
|Defensive aggression in male||Sprague‐Dawley rat, CD‐1 mice; developmental, oral||Increased||Farabollini et al. ; Kawai et al. |
|Hyperactivity, hyperlocomotion and rewarding response||Mice, rats; adult, developmental, oral, injection||Increased||Mizuo et al. ; Suzuki et al. ; Narita et al. ; Ishido et al. |
|Passive and active avoidance learning||Fisher 344 rats; developmental, oral||Impaired||Negishi et al. |
|Maternal behaviour in females||CD‐1 mice, rats; adult, developmental, oral||Decreased||Palanza et al. ; Della Seta et al. |
|Play behaviour in juveniles||Sprague‐Dawley rats; developmental, oral||Decreased||Farabollini et al. |
|Sex differences in behaviour||CD‐1 mice, rats; developmental, oral||Lost||Fujimoto et al. ; Palanza et al. ; Rubin et al. |
2.1.5. Other miscellaneous effects
There are evidences on effects of BPA on subsequent activity of enzymes in tissues and thus metabolic processes [66–69]. Study showed very low dose (10 μg/kg) of BPA stimulates insulin production and secretion, which is then followed by insulin resistance at a dose of 100 μg/kg in mice . In the study by Sakurai et al. , a high dose of BPA has been revealed to stimulate an increase in the glucose transporter and glucose uptake into adipocytes in cell culture. Study showed that perinatal exposure to a low dose of BPA increased adipogenesis in female rats at weaning .
BPA appears to possess complex immuno‐modulating effects. It may stimulate or suppress the immune system. It may also alter immune response pathways. There is extensive evidence that BPA modulates both T helper 1 and T helper 2 cytokine production and alters antibody production [73–75]. Yamashita et al.  used immune cells from BALB/c mice and demonstrated that BPA induces innate immune response by increasing cytokine synthesis, including tumour necrosis factor (TNF) and IL‐1 in macrophages, and stimulates both T and B cells in adaptive response pathway. Using IL‐2 and IFN‐γ as markers for Th1 response and IL‐4 for Th2 response, the authors found that BPA stimulated Th1 cells to produce IFN‐γ and Th2 cells to express IL‐4. The authors inferred that BPA does not selectively activate the Th1 or Th2 path. BPA also enhances Th1 or Th2 response
2.2. Studies on zebrafish
|Hatching, axial curvature, tail morphology||Fertilized eggs, directly in a plate||Delayed hatching, altered axial curvature, tail malformation||Hua and Lin |
|Early dorso‐ventral patterning, segmentation and brain development||Embryo, directly in a plate||Altered||William et al. |
|Fertilization and egg production||Breeding adult, in aquarium||Reduced rate of fertilization, increased egg production||Laing et al. |
|Testes||Adult, in aquarium||Degenerated, increased number of sustentacular cells, decreased percentage of germ cells||Lora et al. |
|Ovary||Adult, in aquarium||Deteriorated ovarian tissues, increased number of atretic follicles, distorted and less developed oocytes||Yon and Akbulut |
|Transcription of genes involved in reproductive function||Adult,||Altered||Laing et al. |
|Oocyte maturation||Adult, in aquarium||Disrupted||Fitzgerald et al. |
|Hypothalamus||Embryo, directly in culture plate||Increased neurogenesis and hyperactivity||Kinch et al. |
|Larval hyperactivity, Adult learning behaviour||Embryo, directly in culture plate||Increased activity, learning deficit||Saili et al. |
|Oocyte maturation||Adult, in aquarium||Disrupted by chromatin modification||Santangeli et al. |
2.2.1. Effects on development and reproduction
Laboratory studies showed that BPA causes developmental and reproductive effects in zebrafish. There are evidences of delayed hatching, altered axial curvature and tail malformation in zebrafish embryos following exposure of fertilized eggs to BPA . In a study by William et al. , BPA altered early dorso‐ventral patterning, segmentation and brain development in zebrafish embryos at a concentration of 50 μM within 24 hours of exposure. Perturbations in expression of cytochrome P450 aromatase activity have also been observed in zebrafish. Estrogen synthesized in the brain by the action of P450 aromatase is known to have organizing effects on the developing central nervous system. In fish, estrogen increases the predominant brain isoform (P450aromB), implying that xenoestrogens like BPA could act as neurodevelopmental toxicants by altering the expression of P450aromB .
Lora et al.  found several alterations in the zebrafish testes including a pronounced degeneration of all cellular components, an increase in the percentage of the Sertoli cells and a marked decrease in the percentage of germ cells due to exposure of BPA. Histological studies also showed severe deterioration of ovarian tissue such as disintegration of vesicular structures of mature oocytes, irregularities at cytoplasm, reduction in the number of primary and developing oocytes, deformation at the ooplasm and structure of the mature oocytes and irregularities at nucleolus. The number of the atretic oocytes increased due to BPA exposure. Structurally distorted and less developed oocytes were also observed . A study by Laing et al.  documented significant increase in egg production, together with a reduced rate of fertilization in zebrafish exposed to BPA, associated with considerable alterations in the transcription of genes involved in reproductive function and epigenetic processes in both liver (vtg1, esr2b, hdac3, mbd2, mecp2 and dnmt1) and gonad tissue (esr2a, cyp19a1a and amh). Their study demonstrated how BPA disrupts reproductive processes in zebrafish. BPA can also disrupt zebrafish oocyte maturation by a novel nongenomic estrogenic mechanism . BPA exerts this nongenomic estrogenic action on zebrafish oocytes directly through binding to the membrane estrogen receptor Gper and activating a Gper‐dependent Egfr/Mapk3/1 pathway. BPA activates this pathway by increasing phosphorylation of Mapk3/1and cAMP concentrations in zebrafish oocytes. Activation of this pathway prevents the resumption of meiotic maturation in fish oocytes . Study showed that BPA downregulated oocyte maturation‐promoting signals through changes in the chromatin structure mediated by histone modifications in zebrafish .
2.2.2. Effects on nervous system and behaviour
Zebrafish has been used extensively to elucidate basic mechanisms underlying behavioural toxicology . Zebrafish was also employed as a model for identifying sex‐specific effects on social interactions induced by developmental BPA exposure [87, 88]. A study by Kinch et al.  revealed that treatment of embryonic zebrafish with very low‐dose BPA (0.0068 μM, 1000‐fold lower than the accepted human daily exposure) resulted in 180% increase in neurogenesis within the hypothalamus. Fish embryos exposed to BPA exhibit hyperactivity with ontogenetic growth possibly due to the accelerated neural growth. The authors also found that these effects are probably not due to an effect on estrogen receptors (or estrogen‐like receptors) but may be due to its deleterious effects on the synthesis of key enzyme in steroid hormone synthesis, Aromatase B. This study also demonstrated that developmental BPA exposure led to larval hyperactivity or learning deficits in adult zebrafish . There are evidences for temperature‐specific impairment of swimming performance, disturbances in muscle activity and gene expression in zebrafish due to exposure of BPA . This result suggests that BPA toxicity is compounded with the effects of climate change.
2.2.3. Other miscellaneous effects
BPA can alter sex ratio of zebrafish by inducing feminization of the fry . Zebrafish embryos exposed to BPA also showed signs of feminized brains . Kinch et al.  investigated morphological changes to developing zebrafish caused by exposure to BPA including changes in body length, pericardia (heart) and the head. Na et al.  observed a significant damage in the liver of zebrafish after 96 hours of exposure to BPA. This result further confirmed that liver was the target organ of BPA.
3. Invertebrate model animals
3.1. Study on
3.1.1. Effects on life history traits and developmental event
In comparison to other studies on effects of BPA on biological aspects in
Another study on life history traits of
3.1.2. Effects on behaviour and nervous system
BPA causes  behavioural modifications in
A recent study conducted by Streifel  shows that administration of BPA in the prenatal environment had significant impacts on some aspects of
3.1.3. Effects on global gene expression profile
Alteration in gene expression profile in
3.2. Study on other invertebrate model
As compared to vertebrates, the number of research works regarding BPA exposure on invertebrates is minimum. Invertebrates are frequently used as bioindicators for endocrine‐disrupting chemicals. Research suggests that some invertebrates appear to be quite sensitive to BPA, and effects have been documented even at environmentally relevant concentrations .
3.2.1. Effects on life history traits and developmental events
A study conducted by Lemos et al.  revealed that low BPA concentrations disrupt the endocrine function of terrestrial arthropod
The effects of various concentrations of BPA on the development of two sea urchin species
Studies on lepidopteran corn stalk borer
A study conducted on
3.2.2. Effects on reproductive system and fecundity
As far as published literatures are concerned, several studies have been conducted to unravel the adverse effects of BPA on reproductive systems and reproductive functioning in various invertebrate animals. In the study of Manshilha et al. , an increased fecundity (neonates per female), in comparison with the negative control group (100.3 ± 1.6%), was observed when daphnids were cultured and allowed to breed in the polycarbonate (PC) containers (145.1 ± 4.3%–264.7 ± 3.8%) for single and multiple generations. A strong dose‐dependent ecotoxicological effect was evident, and it was suggested that BPA leached from plastic materials acts as functional estrogen
Andersen et al.  found an increase in egg production in copepod
|Species||EC50 (mg/L)||NOEC (mg/L)||Reference|
|Waterflea Daphnia magna||10.2||4.1||Alexander et al. |
|Mysid Mysidopsis bahia||1.1||0.51||Surprenant |
|Chironomid Chironomus tentans||2.7||1.4||Mihaich et al. |
|Copepod Tigriopus japonicus||4.32||3.5||Marcial et al. |
|Snail Marisa cornuarietis||>4.03 (LC50)||1.32||Mihaich et al. |
|Snail Marisa cornuarietis||2.24 (LC50)||1.18||Mihaich et al. |
3.2.3. Effects on gene expression profile
Change in expression pattern of genes and alteration in RNA expression pattern due to BPA exposure are also within the scientific interest. Planelló et al.  studied the effects of BPA on the expression of some selected genes, including housekeeping, stress‐induced and hormone‐related genes in
Significant level of DNA strand break has been detected in snail
Bisphenol‐A (BPA), found ubiquitously in our environment, has received a tremendous amount of attention from research scientists, government panels and the popular press. Extensive investigational work has been and is still being carried out in various fields like: (1) mechanisms of BPA action; (2) levels of human exposure; (3) routes of human exposure; (4) pharmacokinetic models of BPA metabolism; (5) effects of BPA on exposed animals and (6) links between BPA and cancer. BPA interferes with hormone signalling via two mechanisms: altering the availability of ovarian hormones and altering binding and activity of the hormone at the receptor level [120–122].
Besides understanding the probable human health hazards, study of BPA effect on model organisms facilitates our concern to the issues like biodiversity loss, environmental degradation and overall imbalance in ecological functioning. Today’s world is extremely dependent on plastics, and this dependency inevitably brings the challenges of BPA exposure to the environment. Invertebrate and vertebrate fauna from terrestrial and aquatic ecosystems get affected equally, and the situation is going worse every day. Tantalizingly, the role of BPA in biodiversity loss is not being analysed when the issue comes on the table for discussion. So, mass awareness is to be build up among the people that include students, scholar, academician, conservationist, wildlife activist, NGOs working with environmental issues, policy‐makers and politicians across the nation. It is hard to make BPA free world, but the extent of its adverse effect could be mitigated by our concern and consciousness.