Contact Us
Chengguan District, Lanzhou, Gansu, China
© 2025 Jeifer Pharmaceutical, All Right
Reserved.
A hundred years ago, castor oil seemed like a staple in any pharmacy—mostly for digestive complaints or as a base for ointments. Scientists noticed early on that pure castor oil didn’t always play well with other materials, especially those found in more complex pharmaceutical products. This sparked efforts to tweak its chemistry. The addition of ethylene oxide led to the development of what we now call polyoxyethylene castor oil. These new derivatives caught attention in the middle of the twentieth century. Factories in Europe and the United States began producing it in large amounts, standardizing grades for pharmaceutical use under BP, EP, and USP monikers. The continued refinement paralleled the explosive growth in drug development, with the pharmaceutical-grade product landing in more and more formulations.
Polyoxyethylene castor oil, especially the Co40 type, solved real problems in suspending drugs and helping them dissolve in water. Drug manufacturers tend to reach for this excipient because it easily binds oil and water, handles sensitive drug molecules with care, and keeps the final product stable long enough to make a difference on a pharmacy shelf. People who work with injections or oral solutions want products to be consistent every time: this fix helps. But that’s only the beginning. Its ability to keep vitamins and other oil-based actives uniform in suspension led to wide use across supplements and even food products. There’s a world of difference between a product that clumps or separates and one that quietly does its job.
At room temperature, this oil-based substance stands as a thick, yellowish liquid. Those who handle it in labs recognize a faint, characteristic odor—hard to describe, but distinct—and its viscosity makes pipetting awkward without practice. With a molecular structure featuring around 40 ethylene oxide units per castor oil backbone (“Co40”), the product’s hydrophilic-lipophilic balance (HLB) sits comfortably high, usually in the range of 13-15. That’s a sweet spot for combining oil and water. It dissolves in water far better than castor oil itself, while keeping a strong affinity for fats.
Manufacturers label it under standards outlined in BP, EP, and USP pharmacopeias. Anyone familiar with regulatory filings knows these acronyms matter across borders. Typical specs include an acid value lower than 2, a saponification value between 50 and 60, and a specific gravity of about 1.06 to 1.08. The labeling plays an important role. It must indicate the grade, batch number for traceability, and origin. Labels must flag whether it’s Co40, purity level, and other relevant safety warnings. Regulatory audits focus not just on what’s inside the container, but whether the labels follow the rules. In pharma, getting that piece wrong can stop a product from entering a market.
Preparation starts with a good batch of natural castor oil, pressed and filtered. The process involves careful mixing of castor oil with ethylene oxide under controlled temperatures and pressures. Skilled chemists control the reaction with precision to ensure the right number of polyoxyethylene chains attach to the triglyceride backbone. If the reaction runs too long, unwanted byproducts show up; cut it too short, and the oil fails to dissolve properly in water. The finished batch heads to purification and quality control, leaving very little residue of reactants. Workers check each batch for water content, appearance, and the signature chemical fingerprints before packaging.
Polyoxyethylene castor oil isn’t just a static molecule. Chemical tweaking has produced grades with varying ethoxylation levels, modifying how the product behaves in pharma and cosmetics. Some labs try partial hydrogenation to stiffen the oil or adjust its resistance to oxidation. The polyoxyethylene side chains open up possibilities for further derivatization—science-speak for attaching functional groups, such as phosphate or sulfate, which shift solubility, surfactant activity, or compatibility with sensitive actives. Each change brings its own regulatory and safety testing burden.
You’ll see this product called polyoxyl 40 hydrogenated castor oil, PEG 40 castor oil, Cremophor EL (from BASF), and Kolliphor EL. The maze of names confuses newcomers, and it pays to double-check product data sheets rather than trust what a supplier says offhand. Pharma companies rely on documentation showing a specific manufacturing process or compliance with a required standard before they add it to their drug products.
Anyone handling Co40 in bulk wears gloves and safety glasses. Accidental spills create slippery floors, but the risks run deeper than basic hygiene. The ethoxylation process can leave trace impurities, such as free ethylene oxide or 1,4-dioxane—both tightly regulated in pharmaceuticals. Regular testing checks purity and lack of contaminants. The pharmaceutical industry follows good manufacturing practice (GMP) for every step, using validated cleaning methods for tanks and observing strict environmental controls when moving or mixing the product.
Polyoxyethylene castor oil’s main home is in drug formulations needing oil and water to play nicely. Injectable drugs, aqueous vitamin solutions, and emulsified oral liquids all benefit from its surfactant power. Chemists add just enough Co40 to dissolve a tough hydrophobic molecule, avoiding uncomfortable reactions at injection sites. Eye drops, creams, and ointments carry the excipient too, seeking convenience and patient comfort. Vaccine makers and biotech labs use it to keep delicate proteins intact, helping the next generation of therapies reach patients without breakdown or clumping. Cosmetic chemistry leans on it for high-end lotions and serums, counting on both gentleness and compatibility with essential oils and other natural actives.
The R&D pipeline shows no signs of slowing. Scientists track every impurity and reaction byproduct, using advanced chromatography and spectroscopy for ever-tighter quality control. Efforts to lower trace contaminants—such as oxidative byproducts and residual ethylene oxide—reflect both better science and legal pressure from regulators. Some teams try to swap castor oil for other vegetable oils, hunting for better patient tolerance or lower allergy risk. The rise of biologics inspires tweaks in the polyoxyethylene structure, aiming to protect protein and peptide drugs in their sensitive liquid forms. All these adjustments stem from real challenges in drug stabilization, bioavailability, and tolerant delivery routes.
Researchers don’t take safety for granted. Cremophor EL, the best-known pharma grade, has a history of causing allergic reactions in some patients—an issue that spurred many hospital protocol changes. Reports of anaphylactoid reactions during chemo infusions led to careful monitoring and dosing adjustments. Studies persist, focusing on protein-drug compatibility, breakdown of the surfactant under storage, and links to rare immune complications. Some research digs into chronic exposure for health care workers or consumers, but the sharpest focus remains on patient safety, especially for drugs that deliver over long periods or via sensitive routes like intravenous infusion. Regulators review every change in formulation with these risk profiles in mind.
The future points to ever-stricter purity demands from regulators, newer surfactant variants with custom properties, and smarter technologies for surfactant recovery and reuse. Synthetic biology hints at vegetable oil backbones engineered for more predictable reactions and higher yields. Researchers watch advances in biopharmaceuticals and gene therapies, where new delivery challenges stretch the limits of current excipients. On the sustainability front, pressure rises to limit or replace petrochemical ethylene oxide with greener feedstocks, which would push the material even further into the future of clean and responsible drug-making. As medication types grow ever more complex, excipients like polyoxyethylene castor oil will see new scrutiny—not just for what they help deliver, but also for how they shape the journey from lab bench to bedside.
Anyone who’s ever read the label of a liquid medicine or eyedrop solution has probably seen some mysterious ingredients. Polyoxyethylene Castor Oil CO40, often called PEG-40 hydrogenated castor oil, shows up far more often than most people realize. It’s a mouthful, but this stuff isn’t just filler. In my years dabbling with pharmacy compounding and following pharmaceutical trends, I’ve seen CO40 emerge as a quiet workhorse in both small clinics and massive production settings.
You won’t often hear people in waiting rooms talk about solubilizers, yet they run into them every time there’s a prescription for a cough syrup, vitamin drops, or an allergy suspension. Polyoxyethylene Castor Oil CO40 takes oil-based drugs and holds them in water-based solutions. That’s not a small trick. Many important drugs, like cyclosporine for eye inflammation or some vitamins, simply won’t dissolve on their own in water. If the drug floats to the top or clumps at the bottom, good luck getting the right dose. It’s like buying a cake mix with all the chocolate chips sunk — you’re not getting what you paid for in every slice.
My first exposure to CO40 came in the back of a pharmacy, mixing up something for a local pediatrician. Kids, in particular, need precise dosing and gentler solutions. CO40 doesn’t just stop at cough syrups; it pulls its weight in injectable medicines too, often helping deliver complicated compounds that must be evenly blended to work safely. The risks from poorly mixed injectables are obvious: pain, inflammation, worse side effects, and sometimes spoiled drugs. PEG-40 prevents those problems by keeping everything uniform.
Pharmaceutical grades like BP, EP, and USP mean this version of castor oil derivative has to stay squeaky clean. Manufacturers test for contamination, heavy metals, and unexpected byproducts. A lot of fresh pharmacy graduates ask if this level of scrutiny really matters. It does. Anything injected, swallowed, or used on broken skin can cause a problem if contaminants sneak in. The track record of CO40 in major brands speaks for itself. It’s part of why regulatory bodies around the world approve its use in sensitive products.
There’s always chatter about allergies or plant-source ingredients. CO40 comes from castor oil, which naturally contains ricin in raw form—one of the most dangerous toxins out there. But the chemical processing strips that away. I’ve witnessed several product recalls caused by cross-contamination of natural oils that weren’t as thoroughly purified. With PEG-40, severe allergic reactions almost never crop up. Still, patients or doctors who question the source, whether for religious, ethical, or allergy reasons, deserve straight answers from suppliers.
Every conversation about pharmaceutical ingredients right now includes talk of sustainability and alternatives. Polyoxyethylene castor oil isn’t perfect. Production involves petroleum derivatives, and the world of green chemistry keeps moving forward. Some researchers are working on new plant-based solubilizers and surfactants that cut down on petrochemical inputs. Regulatory agencies give companies some leeway, though every new substitute still gets a tough round of testing. For now, CO40 sticks around because it simply works.
Patients trust that medicine works as promised. That confidence relies on ingredients like Polyoxyethylene Castor Oil CO40 doing their job behind the scenes every single time, whether you’re pouring out a teaspoon for a child, squeezing out a lotion, or getting a dose through an IV. Not every ingredient gets the attention of a wonder drug, but without CO40, the shelves would look pretty empty.
Polyoxyethylene Castor Oil Co40 holds an important spot in fields like pharmaceuticals and cosmetics. Most folks might just look at it as a chemical name on an ingredients list, but this nonionic surfactant makes a noticeable difference in product stability and performance. Known commonly as PEG-40 Hydrogenated Castor Oil, it comes from natural castor oil transformed through hydrogenation and the addition of polyethylene glycol units.
Looking at the nitty-gritty, Polyoxyethylene Castor Oil Co40 contains approximately 40 ethylene oxide units per molecule. This long chain increases its water solubility—castor oil in a form that mixes much more easily with water. Its appearance usually stands out: a pale yellow, viscous liquid or sometimes semi-solid paste, depending on storage conditions and temperature. The product gives off little to no odor, which makes it popular in applications where scent can ruin the end result.
The Hydrophilic-Lipophilic Balance (HLB) value often sits around 14 to 16. For those who have worked in compounding or lab settings, this HLB value tells a lot: it signals a strong affinity for water, so it helps blend oil-based components with water-based solutions. Most emulsifiers fall on a sliding scale, and Co40 tips the scale toward stabilizing oil-in-water mixes. Viscosity ranges somewhere between 3000 to 7000 centipoise at room temperature, which means it pours slowly but still can be worked with using standard equipment.
Many formulators lean on Co40 for its solubilizing abilities. Take an oil-based vitamin, for example—Co40 lets it disperse evenly in a water-based drink or liquid medicine. I’ve seen supplement makers use this surfactant to keep active ingredients from floating or clumping, which matters if consumers need consistent dosing. In topical creams or lotions, it’s not just about keeping oils and actives from separating. It prevents cloudy layers from forming, keeping products looking and feeling smooth, which boosts trust.
It doesn’t just play a behind-the-scenes role. With better solubility, drug absorption gets a subtle boost—meaning medications can kick in a bit stronger or faster. In food science, it acts this same way to help flavors or vitamins mix into beverages without turning murky.
Years of data show Polyoxyethylene Castor Oil Co40 features low toxicity and remains stable at a wide range of pH values, typically from 3 up to 10. This versatility supports safe use in medicines, creams, drinks, and even soaps for sensitive skin. It resists hydrolysis and oxidation pretty well, giving finished goods a longer shelf life. Most regulators, including the US Food and Drug Administration and the European Food Safety Authority, have given it the stamp of approval for specific uses—provided limits aren’t exceeded. Reports of side effects are rare, and allergic responses tend to come from impurities, not the emulsifier itself, according to studies posted in toxicology journals.
One key limitation involves its origin—it’s based on castor oil, which means it’s not a solution for patients with rare castor oil allergies. Formulators can look toward synthetic or alternate botanical sources if allergies arise in certain populations. Residual impurities from the manufacturing process occasionally cause quality concerns. Analytical testing, like gas chromatography or HPLC, picks up these trace impurities and helps ensure product safety. Supply chains for the raw ingredients sometimes face volatility, which highlights the need for diversified sourcing and backup suppliers.
Careful selection and testing help avoid surprises in large-scale production. For brands, clear labeling and transparency support consumer confidence. Technical staff working directly with Co40 have seen strong results by using strict quality control and adjusting pH and other factors as needed.
A lot of folks in pharmaceutical labs use Polyoxyethylene Castor Oil Co40 as an emulsifier. It's what lets oily and watery stuff come together in things like syrups, creams, and injections. If you’ve ever mixed oil and water for salad dressing, and added a bit of mustard or egg yolk, you’ve used the basic idea of an emulsifier. Co40 works the same way in medicine, but you won’t find any eggs here.
Formulators blend loads of ingredients—each with its own quirks. Toss Co40 into the mix, and you want it to help, not mess up. Some folks assume every emulsifier plays friendly with everything else in the recipe. I’ve seen attempts where the whole thing curdled, separated, or went cloudy, all because someone forgot that tiny details matter. If you get compatibility wrong, the end product turns unstable and sometimes flat-out unusable.
I’ve seen some drug makers blend Co40 with hydrophilic (water-loving) drugs like acetaminophen or some vitamins, and get a stable, clear product. Co40 has a strong track record with water-based solutions, and it has helped in both oral and injectable forms. People like it because it has a long history of safe use when made and used properly. Co40 has even found a home in cancer drugs where it helps to dissolve tricky compounds like paclitaxel.
Here’s where the story sours a bit. A few ingredients just can’t get along with Co40. The issue starts with charge and chemical structure. Strong acids, some alkalis, and certain salts seem to upset the balance, making the product separate or throw off particles. If you put a basic drug together with Co40, the result can be cloudy or gritty. Certain preservatives, parabens for one, sometimes break the emulsion.
There’s the infamous issue with protein-based drugs. Co40 may denature (wreck) proteins, so you can't throw it into every peptide or hormone formula and expect it to work. I watched a batch go south in a protein suspension; adding Co40 wrecked the active ingredient.
Testing beats guesswork every time. Researchers use stress tests—heat, shaking, light—to see what happens over time. Regulatory agencies like the FDA and EMA expect full compatibility studies, not just a quick mix-and-see. Some institutions print their results, so others can learn from those mistakes and successes.
Start small: combine all components in simple water-based solutions and watch for changes. Move on to more complex mixtures, always keeping an eye on changes in appearance, pH, and smell. I've seen manufacturers add stabilizers or switch the order of mixing, sometimes solving issues with a simple adjustment.
New surfactants and co-emulsifiers hit the market each year, offering more tailored compatibility for sensitive or new pharma compounds. Analytical tools like HPLC and particle size analysis help spot trouble sooner, so teams can catch issues before a full production run.
What counts most is a clear understanding of how each ingredient interacts at the molecular level. Start with the finished product in mind, and don’t take shortcuts with compatibility testing—your patients, your colleagues, and your own reputation count on getting it right.
In the world of excipients and emulsifying agents, Polyoxyethylene Castor Oil Co40 gets regular use. Its job in blending otherwise incompatible ingredients together makes it valuable in medicine and personal care products. Over the years I’ve seen that the way this material is kept on the shelf often shapes how well it performs, not just in theory, but in real operation. Quality matters. That starts with where and how you stash it.
The formula tends to pick up moisture if left open or in a humid warehouse. Leaving drums uncapped or exposed to warehouse air could cause clumping or cloudiness. Moisture messes with viscosity and impacts blending—leading to headaches down the road during production. A tight lid after use stops this problem before it starts.
A steady temperature keeps Polyoxyethylene Castor Oil Co40 in top form. Once temperatures dip, this liquid may turn cloudy or even solidify. Freezing ruins the pour and can cause layered separation. Anything below 15°C (59°F), and it starts to thicken up, so most facilities keep it between 18–25°C (64–77°F). Direct sun or a room with quick swings in temperature creates more problems than it solves—products lose their shelf life quickly if the oil gets baked by sunlight or forced to keep melting and freezing. Regular room temperature storage means no rushing to warm drums up or dealing with failed batches.
The product arrives in high-density polyethylene or stainless steel drums for good reason. Steel drums without a proper lining can rust, and leach unwanted bits into your oil. Cheap containers not designed for chemicals can deform, leak, or break down after a few months. It pays to use the container supplied by the trusted provider as they know what can handle the product’s chemical nature. In my experience, switching from one drum to another usually means more exposure, spills, and wasted product. It’s safer—and more cost-effective—to only open and decant what’s needed.
Anyone moving drums of castor oil derivatives learns quickly that the viscosity jumps higher as it cools. Pouring cold, thick oil is asking for spills or strain injuries. A drum heater wrap or keeping the storage room at the right temperature protects staff from struggling with a stubborn drum. Open the container gently to relieve any vacuum, and wipe up every drop—they create slipping hazards or sticky messes that take time to clean.
Splash goggles and nitrile gloves matter here. Despite being known for use in pharmaceuticals, this oil-based material can irritate skin with repeated exposure. Once you see an employee forget gloves and get sticky hands for the rest of the morning, the reason for PPE gets obvious.
Facilities that keep storage areas clearly labeled avoid mix-ups. Blending mistakes cause costly reworks and may put patient safety at risk in a manufacturing setting. Keeping logs of batch numbers and opening dates gives a clear line of traceability, which speaks directly to compliance with Good Manufacturing Practice (GMP) standards.
From my experience, the sites that take these steps seriously end up with fewer product recalls and less wasted product. It’s not fancy new tech, but steady attention to detail pays off with every batch made.
Plenty of us don’t notice ingredients like Polyoxyethylene Castor Oil Co40. It’s one of those names that slips past the average shopper, buried in medicine labels or food additive lists. In my own kitchen, I’ve found myself squinting at packaging, trying to figure out what’s hiding behind the chemical lingo. Co40 usually stands out in the pharmaceutical world, playing its part as a solubilizer, which basically helps oily ingredients mix well with water. Some folks also call it Cremophor RH40, and it's developed a reputation for being a multi-tasker. But the nagging question remains: is it safe to eat?
The top question is usually whether a substance meets the standards of pharmacopeias like the USP, EP, or JP. Pharmacopeial standards act as a checklist for purity, harmful chemicals, and heavy metals. Polyoxyethylene Castor Oil Co40 has a monograph in the United States Pharmacopeia (USP-NF), which means researchers have mapped out its quality requirements. The standards go well beyond just limiting what shouldn't be there; they describe what absolutely must be present to qualify as pharmaceutical grade.
I’ve watched the pharmaceutical industry rely heavily on these benchmarks to shield patients from contamination, whether we’re dealing with life-saving drugs, vaccines, or tablets for headaches. Experience taught me that if a supplier cannot show pharmacopeial compliance with solid certificates, you just don’t use it in medicine—full stop. The USP-NF, European Pharmacopeia, and Japanese standards all demand tests for peroxide, acid content, and limits for ethylene oxide or heavy metal residues. A non-compliant batch gets rejected. That’s about as serious as it gets in manufacturing.
The FDA’s Generally Recognized As Safe (GRAS) list includes Polyoxyethylene derivatives in food-type applications, usually in tiny amounts. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) draws a similar conclusion at doses below 25 mg/kg body weight per day. For medicines, the safety tests involve much more detail, including chronic use, reproduction toxicity, and effects on the immune system. One point that scientists flag: very high doses might cause reactions—sometimes allergies or gastrointestinal discomfort—especially in drug infusions.
I remember reading journal articles about Cremophor RH40 in anti-cancer drugs, where higher volumes led to allergic flare-ups in a small number of patients. These problems rarely show up in consumer medicines or food, since product formulations stick far below risky levels. Still, the stories reveal an important lesson: even something with a long safety record demands thoughtful review each time someone changes the recipe or increases the dose.
From my time working with pharmacists, doctors, and food scientists, I’ve noticed how critical transparency becomes. Manufacturers must share batch-specific purity data, and consumers deserve plain-language explanations of the risks—even minor ones. Some labels tell you more about what’s not inside than what is, and that only adds to confusion. Better info empowers people to make sensible choices, whether you’re a patient or just someone who likes knowing what’s in your smoothie packet.
In the end, you gain a clearer picture of Polyoxyethylene Castor Oil Co40 by looking for its most recent pharmacopeial status, reviewing the supplier’s documentation, and keeping your ear to the ground for new safety studies. That’s how you put both comfort and caution into the food or medicine routine. Choice improves with honest information—something everyone can appreciate, especially in a world full of complex-sounding ingredients.
| Names | |
| Preferred IUPAC name | Polyoxyl 40 Hydrogenated Castor Oil |
| Other names |
Cremophor EL Polyoxyl 35 Castor Oil PEG-35 Castor Oil Polyethylene Glycol 35 Castor Oil Macrogol 35 Castor Oil Polyoxyethylated Castor Oil |
| Pronunciation | /ˌpɒliˌɒksiˌiːθɪliːn ˈkæs.tər ɔɪl siː oʊ ˈfɔːrtiˈbiːpiː iːˈpiː ˈjuːˈɛsˈpiː ˈfɑːmə ɡreɪd/ |
| Identifiers | |
| CAS Number | 61791-12-6 |
| Beilstein Reference | 3727934 |
| ChEBI | CHEBI:53427 |
| ChEMBL | CHEMBL1201561 |
| ChemSpider | 21544145 |
| DrugBank | DB11096 |
| ECHA InfoCard | ECHA InfoCard: 100.024.763 |
| EC Number | 61791-12-6 |
| Gmelin Reference | Gmelin Reference: **145108** |
| KEGG | C14422 |
| MeSH | Polyoxyethylene Sorbitan Esters |
| PubChem CID | 5284442 |
| RTECS number | WGK3 |
| UNII | 2DR64RWG9U |
| UN number | UN3082 |
| CompTox Dashboard (EPA) | CompTox Dashboard (EPA) of product 'Polyoxyethylene Castor Oil Co40 BP EP USP Pharma Grade' is "DTXSID8037823 |
| Properties | |
| Chemical formula | (C₂H₄O)n·C₅₇H₁₀₀O₉ |
| Molar mass | ~2500 g/mol |
| Appearance | Pale yellow oily liquid |
| Odor | Characteristic odor |
| Density | 1.05 g/cm³ |
| Solubility in water | Soluble in water |
| log P | 2.9 |
| Acidity (pKa) | ~4.5 |
| Basicity (pKb) | 8.0 (pKb) |
| Refractive index (nD) | 1.46 – 1.48 |
| Viscosity | Viscosity: 300 - 500 cP |
| Dipole moment | 1.45 D |
| Pharmacology | |
| ATC code | A06AG11 |
| Hazards | |
| Main hazards | May cause eye and skin irritation. |
| GHS labelling | GHS07, GHS08 |
| Pictograms | GHS07, GHS08 |
| Hazard statements | No hazardous statements. |
| Precautionary statements | P280: Wear protective gloves/protective clothing/eye protection/face protection. |
| NFPA 704 (fire diamond) | 1-1-0 Health=1, Flammability=1, Instability=0 |
| Flash point | > 220°C |
| Lethal dose or concentration | LD50 (rat, oral): > 4,000 mg/kg |
| LD50 (median dose) | > 7.36 g/kg (oral, rat) |
| PEL (Permissible) | PEL (Permissible Exposure Limit) for Polyoxyethylene Castor Oil Co40 BP EP USP Pharma Grade is not specifically established by OSHA or other major regulatory agencies. |
| REL (Recommended) | 40 mg/kg |
| IDLH (Immediate danger) | Not Established |
| Related compounds | |
| Related compounds |
Polyoxyethylene hydrogenated castor oil Cremophor EL Polyoxyl 35 castor oil PEG-35 castor oil Polyethylene glycol castor oil Polyoxyethylated glycerides |
Chengguan District, Lanzhou, Gansu, China
