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Dibutyl Phthalate stands out as one of those chemicals that has tracked alongside industrial progress for over a century. Early records point to its development in the late nineteenth and early twentieth centuries, right as industrial chemists started searching for better ways to make polymers flexible without losing their basic strength. Over time, the pharmaceutical, cosmetic, and plastics industries embraced this compound, noticing that it solved practical problems others could not touch. In decades past, factories saw Dibutyl Phthalate as a kind of insurance policy for smooth, reliable output, and it held its place in global pharmacopeias because it fit regulations adopted both in Europe and the US. The plasticizer market grew, and so did the knowledge and controversies over its health implications and production methods. I’ve seen how a regulatory update in Europe could ripple through global supply, as buyers and labs had to re-validate sources to withstand audits. Historical use made it indispensable, but changing priorities—especially around patient safety and environmental impact—gave it a new reputation, forcing scientists not just to understand but also to scrutinize its every property.
In the world of pharmaceutical processing, Dibutyl Phthalate doesn't just offer flexibility; it delivers a unique balance between solubility, compatibility, and chemical stability. Markets rely on this compound because it keeps coatings workable and tablet formulations reliable during mass manufacturing. Sellers and buyers often cite its dual approval under BP, EP, and USP grades, offering confidence from raw material purchase through to regulatory submissions. Its chemical fingerprint ensures compatibility with a range of excipients and active pharmaceutical ingredients, and manufacturers often cite it as a gold-standard comparison for new plasticizers. Critical attributes like purity and batch-to-batch consistency push companies to invest in robust analytical controls, and the impact of a contamination scare can send shockwaves across the pharmaceutical industry.
Dibutyl Phthalate sits on the lab bench as a clear, oily liquid with a faint, somewhat sweet odor—almost the kind of substance you remember by both sight and smell. Its boiling point hovers around 340°C, and its density tells you it will sink in water. Chemically, the structure features two n-butyl ester groups attached to a phthalic acid core, making it both flexible for formulation and resistant to rapid breakdown. Its low volatility and solid solvency mean it stays put when added to tablet coatings or films. In the lab, I’ve learned to trust its physical uniformity, but also watched regulatory teams scrutinize every supply lot for even minor shifts in impurity profiles or moisture content.
Quality control teams work hard to uphold technical specifications, keeping close tabs on purity—often above 99.5% on the certificate of analysis. Color is checked using APHA standards, and acid content shouldn’t budge above a few tenths of a percent. Heavy metal residues cause worry for regulatory staff, so strict in-house assays run down sensitivities to the parts-per-million level. Labeling stays direct, highlighting manufacturer, batch number, expiry date, pharma grade status, and all essential handling warnings. On the receiving dock, every container gets a second inspection, because mistakes in labeling or fine print can lead to audits, quarantines, and product recalls.
Producing reliable Dibutyl Phthalate takes more than just reacting phthalic anhydride with n-butanol. Industrial scale-up means managing reaction temperature, controlling by-product formation, and driving the synthesis to full esterification. Acid catalysts push the process forward, and water removal steps ensure better conversion rates. Purification isn’t just a matter of filtration but of repeated distillation, stripping out low-boiling contaminants and high-boiling tars. Waste minimization, especially around water handling and catalyst residues, presents major challenges for anyone aiming to meet GMP or EU regulatory standards. Refinements in this process keep supply chains reliable and prices stable, but the demand for higher environmental stewardship now places more responsibility on chemical plants to recycle, reduce energy use, and manage emissions tightly.
Dibutyl Phthalate shows a reluctance to take part in side reactions under normal conditions, which is why it works so well in pharmaceutical coatings and adhesives without breaking down or forming unpredictable by-products. Its ester linkages can hydrolyze in strong acid or alkaline environments, and regulatory labs devote whole projects to tracking possible hydrolysis by-products over time and storage. Researchers have modified the molecule to try to improve its environmental profile, sometimes swapping butyl chains or branching the carbon chain to alter bioaccumulation patterns. These efforts to engineer ‘safer’ phthalates often return the same lesson: performance in pharma settings demands chemical resilience and purity that’s hard to beat, but every change creates a cascade of new regulatory and safety hurdles.
You’ll spot Dibutyl Phthalate listed under a handful of names in any warehouse or raw material database: DBP, Di-n-butyl phthalate, 1,2-Benzenedicarboxylic acid, dibutyl ester, and even simple designations like C16H22O4. In some settings, branded versions enter the supply chain, but at the end of the day, experienced buyers and scientists rely on CAS numbers and pharmacopeia IDs to sidestep the alphabet soup of synonyms and ensure clear communication from procurement through to quality control. Any mix-up, especially in a multinational operation, can lead to costly delays, so clarity in documentation remains a dealbreaker.
From first touch, Dibutyl Phthalate commands respect in the lab and in large-scale handling. Safety data sheets underline the need for protective gloves and goggles, and good plant engineering limits worker exposure through closed systems and top-of-the-line ventilation. The biggest headaches I’ve seen arise in bulk transport and storage, when even minor leaks trigger full emergency response protocols and toxicology teams survey the scene for inhalation or skin exposure risks. Strict occupational exposure limits apply in many regions—Europe especially—and regulatory reviews drive regular retraining for plant operators. GMP compliance goes beyond batch release, forcing ongoing attention to container integrity, labeling accuracy, and regular environmental monitoring.
Pharmaceutical technologists keep returning to Dibutyl Phthalate for good reason. It delivers reliable plasticizing action in film coatings for tablets and capsules, preventing cracks and maximizing both package appeal and patient compliance. While it also shows up in adhesives, inks, and sometimes as a solvent for controlled-release formulations, most innovation centers around pharma-grade uses that can withstand regulatory scrutiny and provide predictable results at scale. As regulations tighten around certain excipients, contract manufacturers look for alternatives, but few beat DBP’s history of performance and track record in finished dose forms used for decades.
Labs still dig into the chemistry of Dibutyl Phthalate, looking for ways to replace or reformulate old standbys as regulations shift and public expectations change. Analytical chemists look closely at metabolite tracking, absorption rates, and downstream impurity formation. Toxicologists have developed improved tools for simulating long-term exposure, building datasets meant to guide policy and keep ahead of new regulatory thresholds. Some teams focus on green chemistry modifications, introducing renewable feedstocks or closed-loop systems, though competing on price and performance with legacy production lines remains tough. As researchers push for deeper toxicological understanding, industry partners closely watch each development, bracing for both market shocks and new business opportunities.
Dibutyl Phthalate, once trusted without question, now draws consistent scrutiny from consumer advocates and regulatory toxicologists alike. Animal studies point toward endocrine disruption and reproductive risks at higher exposure levels, setting off rounds of reviews in Europe and the United States. Products meant for children or pregnant women now mostly exclude DBP as a precaution, driving regulatory shifts and lawsuits in some territories. Epidemiological studies still spark debate, but risk managers in pharma companies have little patience for theoretical comfort—regulations demand lower thresholds, clearer documentation, and more comprehensive risk assessments. I’ve seen manufacturing sites ramp up their monitoring, install new safety engineering controls, and partner with academic labs to stay ahead of any negative headlines.
The story of Dibutyl Phthalate is still evolving. Regulatory pathways keep tightening, and pharma companies scan the horizon for next-generation plasticizers with better safety profiles and smaller environmental footprints. New entrants don’t just have to work as well; they need to deliver when scaled up, win regulatory approvals, and enter supply chains without hiccups. I’ve watched startups and multinational giants alike invest in research, pilot new bio-based plasticizers, and reengineer tablets and coatings to minimize long-term health risks for patients and workers. Market demand for safer, “clean label” excipients could redefine DBP’s place in pharma, but legacy operations and historical familiarity with the compound make any wholesale replacement a tough, often generational, project.
Everyday medical products sometimes owe their existence to compounds the average person cannot even pronounce. Dibutyl phthalate, often shortened to DBP, falls into this category. It’s a member of the phthalate family, often known for use in plastics, but its pharma-grade version serves an entirely different purpose compared to industrial forms.
In the pharmaceutical world, DBP in pharma grade usually appears in medicines you swallow and sometimes in coatings for tablets or capsules. Its primary job is to act as a plasticizer. Without a plasticizer like DBP, many tablet coatings would be brittle and would crack under simple physical stress. I’ve talked to pharmacists with years behind the counter, and they’ll tell you: nobody wants to open a medicine bottle and pull out broken pills. A good coating ensures each dose goes down right, keeps moisture away from the sensitive contents, and stops a foul taste from hitting your tongue.
Pharma grade standards go far beyond what’s allowed in factory floors or hardware store shelves. Every molecule of DBP destined for pharma use must meet purity levels that protect patients from impurities or harmful byproducts. Reputable manufacturers follow British Pharmacopoeia (BP), European Pharmacopoeia (EP), and United States Pharmacopeia (USP) guidelines. These standards focus on patient safety, which grows even more important for medicines meant for children or those requiring controlled-release formulas.
Science doesn’t stand still. Researchers over the years have raised concerns about the safety of phthalates in consumer products, including DBP. Studies link chronic exposure to certain phthalates with hormone disruption and developmental issues. Regulatory agencies across the globe, including the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA), now limit the amounts allowed, especially in products intended for pregnant women or young children.
This gives those of us on the front lines of research and development a challenge. Pharmaceutical companies face increasing pressure to find safer alternatives or reduce the use of DBP wherever possible. Some have switched to new plasticizers with improved safety profiles, like triethyl citrate or polyethylene glycols. Swapping out DBP is not just a paperwork exercise; it often demands years of stability testing, patient trials, and changes to manufacturing equipment. Yet, public safety always deserves that investment.
Anyone who’s wrestled with a bitter tablet or watched a child refuse their medication appreciates what DBP brings to the table. Yet, as with so many chemical ingredients, the balance between function and safety cannot be ignored. Transparency in sourcing, strict quality tests, and ongoing clinical evaluations have become part of the modern pharmacist and manufacturer’s job description.
In my own work with medication formulations, I’ve seen how seemingly minor tweaks—like changing a tablet coating’s main ingredient—can ripple across entire production lines. For each solution, drug makers jump regulatory hurdles while reassuring both doctors and patients that their medication remains safe and effective.
Pharma-grade DBP reminds us that even the supporting players in medicine deserve scrutiny. As new research comes down the pipeline and regulatory expectations shift, the healthcare industry adapts. What matters most is putting patient welfare first, encouraging open discussion about ingredients, and supporting the continual search for safer, better tools in medicine.
Dibutyl phthalate, better known as DBP, pops up in the pharmaceutical world far more often than most people realize. This liquid, mostly used as a plasticizer, becomes essential in tablets and capsules, keeping things stable and flexible. The industry looks for DBP that meets BP (British Pharmacopoeia), EP (European Pharmacopoeia), and USP (United States Pharmacopeia) criteria, each one drawing a clear line in the sand about what’s acceptable.
Top-quality DBP comes as a clear, colorless to faintly yellow oil. Strict specifications demand high purity—at least 99% as determined by chromatographic analysis, with water content under 0.2%. The acid value, an indicator of residual acids, stays as low as possible (under 0.15 mg KOH/g). If you ever deal with products that fail these marks, you’ll notice the difference right away. Tablets may turn brittle, coatings can turn sticky, and shelf lives definitely shrink.
BP, EP, and USP grades also clamp down on contaminants. Heavy metals? Less than 10 parts per million. Arsenic? No more than 2 parts per million. These aren’t just numbers to tick off; they’re rules built on decades of experience, recalling times when trace impurities wreaked havoc in finished medicines. If a batch drifts outside these purity limits, the risk isn’t just a failed test. Patient safety comes into play, and regulatory authorities may step in with recalls or penalties.
Years working alongside manufacturers have shown how quality assurance teams never take pharma-grade DBP lightly. Documentation needs to trace each drum back to its source, and every batch should carry certificates of analysis matching the pharmacopeia's latest version.
The specifics matter. A melting point below -35°C and boiling between 340-345°C means DBP keeps its form and function when tablets go through high-speed production and blister packaging. A refractive index of about 1.485-1.489 at 20°C reveals a lot about purity, measuring up to tight standards. Even the flash point, usually above 160°C, tells a safety story—nobody wants unexpected fires near pharmaceutical lines.
Biological tests set another bar. Reputable labs check for residue on ignition and ensure it remains below 0.05%. Manufacturers know if the DBP leaves more behind, it will show up as soot or unwanted deposits, a nightmare during routine audits.
All these checks lower risks. Production stays on schedule, patients trust their medicine, and regulators find clean paperwork if they come knocking. Supply disruptions virtually always trace back to a breakdown in quality or documentation—a story that repeats itself across the globe in aging plants skimping on raw material tests.
Producers who care about their reputation make traceability non-negotiable. Every drum of DBP must follow a clear chain—from supplier, through testing, to deployment on the production floor. In my experience, early investments in chromatographic equipment pay off, uncovering off-spec material before it ruins a production batch and stalls delivery to pharmacies.
Partnerships with suppliers often go well beyond price: regular audits, frequent third-party lab verifications, and shared improvement programs help both sides. As regulators push for ever tighter nitrosamine controls across pharmaceuticals, suppliers who stay up to date with published limits actually help prevent future recalls.
It doesn’t just end with ticking boxes for each specification; building a quality culture pays dividends. One misstep with a batch of DBP, and you don’t just lose product—you risk a reputation that took years to build. This is why sticking to the BP, EP, or USP spec matters for DBP, no exceptions.
Talk to folks in pharmaceutical manufacturing, and they’ll admit that plasticizers play an unglamorous but big role in shaping the tablets and capsules we see daily. Dibutyl Phthalate (DBP), present in the BP, EP, and USP pharma grades, makes pills easier to swallow by giving coatings their flexibility. It stops cracks and keeps ingredients from breaking apart—nobody enjoys swallowing a crumbly mess.
Pharma companies stick to guidelines and batch testing, but one question keeps popping up: Is DBP safe in medicines? The FDA and EMA once signed off on DBP as a harmless helper in coatings, but new findings put phthalates like DBP under a sharper microscope.
Researchers linked DBP exposure to health risks such as hormone disruption, especially in vulnerable groups like children and pregnant women. Regulators started looking for safer alternatives once studies appeared. The European Food Safety Authority (EFSA) tightened daily limits on phthalates, and the FDA also recommends staying within strict safety boundaries.
If you look at the evidence, DBP’s main problem comes from long-term exposure. People who take a chronic prescription with DBP-coated tablets, or children who get dosed over years, may face a higher chance of harm. In 2012, a Harvard-led study found a correlation between phthalate exposure and altered hormone levels in adults. DBP can cross the placenta, and pregnant women don’t want to risk their babies’ health for the sake of a stable tablet.
Pharmaceutical brands must balance product integrity with public health. Nobody wants coatings to break and ruin shelf life, but patients are losing trust after seeing news about chemicals in their medicine. My pharmacist neighbor has seen worried parents ask whether their child’s epilepsy meds contain DBP, especially since kid-friendly liquid versions are hard to get.
Many drugmakers have started reformulating products to phase out DBP, looking for safer plasticizers that meet safety standards and pass stability tests. Some switch to cellulose-based coatings or use polyvinyl alcohol blends. These swaps sometimes cost more, but that’s preferable to fielding lawsuits or product recalls later on.
Drug safety relies on more than just lab tests. Regulators demand full disclosure, but clarity helps everyone in the chain—from doctors to parents picking up refills. If someone relies on a DBP-coated pill, the label ought to reflect that, so people can decide whether the benefits outweigh the risks for them. Open discussion helps protect those with higher risk, while not panicking those with one-off prescriptions.
Pharma has a chance to earn trust by moving quicker than the minimum rules demand. Switching to alternatives may not solve every problem, but acknowledges new science and respects public concern. Just because DBP kept things running smoothly for decades doesn’t guarantee its place in tomorrow’s medicine cabinet. Listening, adapting, and putting patient safety first will ensure that the next generation of drugs delivers healing without hidden costs.
Think about any ingredient in medicine—quality can't play second fiddle. With dibutyl phthalate in pharma grade, purity means everything. I’ve seen production floors where a single careless move around storage turned three days of safe material into waste. To avoid this, suppliers lean on minimum interference. This means closed-loop transfers, lots of stainless steel, and containers designed to ignore the outside world. No one wants product recalls because of a leaky drum.
Dibutyl phthalate, or DBP, doesn’t belong in just any container. High-quality pharma DBP shows up in high-density polyethylene (HDPE) drums or barrels. Sometimes, those drums come lined with a food-grade inner bag or even an aluminum seal to lock out air and moisture. Big players use steel drums lined with epoxy resin for extra muscle against corrosion. For smaller quantities, I’ve seen HDPE carboys with solid, tamper-evident lids. The goal here: block sunlight, lock down the fumes, and stop any chance of accidental spills. Every detail in this packaging process keeps both the product and the people handling it safer.
In pharma, nobody skips over the labeling. Every drum, carboy, or container carries labels with batch numbers, lot codes, expiration dates, and hazard warnings. Clean and easy-to-read labels end confusion on the floor. Regulators like the FDA watch this part closely—mislabel and risk losing a whole shipment at customs or in audit. Tamper-proof seals help spot anything fishy. I’ve seen people lose jobs over unsealed containers because the risk to patients can’t be ignored.
Dibutyl phthalate should never go near a boiler room or sunny loading dock. High temps push it to break down or leach fumes. Top pharma warehouses post visible signs about low light, cool climate, and solid ventilation. I worked in a plant where a forgotten drum near the west window started sweating—no one forgets the smell or the cleaning that followed.
Though DBP has useful flexibility as a plasticizer, no one wants to breathe it in. Modern storage setups park drums away from acids, oxidizers, and open flames. Spill kits hang on every wall. Floors stay smooth—no cracks where leaks can hide. Safety data sheets rest in easy reach, not buried in filing cabinets. Inspectors love to spot chemical safety plans posted in plain sight.
Regulations on DBP tighten every year. I spoke with a warehouse manager who switched to smart sensors tracking every drum’s seal and temperature in real-time—mistakes now cost more than tech upgrades. With new rules on hazardous chemicals, pharma suppliers can’t cut corners. Good training and smart processes keep DBP out of trouble and in top shape for medicine makers.
DBP never gets handled as just another ingredient in the pharma world. Secure packaging, airtight labels, strict storage—every link in the chain plays its part. I’ve learned the hard way: treat these details as afterthoughts, and the knock-on effects get expensive fast. Risk drops and patient safety improves when the industry stays strict on the basics.
Pharmaceutical-grade materials call for more attention than the stuff you find in consumer goods. Dibutyl phthalate, known for its use as a plasticizer, ends up in all sorts of products. Once that same ingredient touches anything related to medicine, standards change. A Certificate of Analysis (COA) isn’t just more paperwork. Think of it like a background check for the chemical. Patients and regulators don’t take chances with hidden impurities. Without a COA, every promise of purity is just words. With it, buyers know the specific batch met clear, written standards—BP, EP, USP. That means international guidelines, not just what a single company says about its shipments.
If you run a business involved in pharmaceutical manufacturing or packaging, you already know every supplier faces regular audits and spot-checks from authorities. Health agencies, from the US FDA to the European Medicines Agency, actively ask for these certificates during inspections. Providing the COA isn’t an option anymore; it’s built into the way companies stay licensed and competitive. If a manufacturer can’t show one on demand, red flags go up. Procurement teams know how quickly a missing document raises eyebrows during internal reviews, too. No COA means shipment delays, expensive product holds, and sometimes, entire batches end up in the waste pile.
People talk a lot about transparency, but it only means something if you show exact numbers and test methods. Here, a proper COA lists every single analyte checked, the test method (such as gas chromatography or HPLC), and results, down to decimal points. Results line up against published pharmacopeia limits—say, for heavy metals or water content. For something as sensitive as Dibutyl Phthalate, suppliers should test for things like purity minimums, identification, acid value, and residue on evaporation. Without these figures, nobody outside the lab can be sure what’s sitting in the container.
There’s a reason companies advertise their willingness to provide a COA before signing any contracts. Supply chains run on trust, and trust builds from past performance plus clear documentation. If you buy from a provider and each order comes with a signed, stamped certificate, you’re more likely to stick with them. Nothing erodes a partnership faster than a surprise visit from a regulator, followed by a frantic call to a distributor who shrugs and says they can’t locate last month’s analysis. The best suppliers offer COAs automatically, without you having to chase after them each time.
Not every supplier meets the same standard. Companies that want repeat business don’t just offer bill-of-sale receipts—they keep detailed test results for every lot. The push for better safety flows straight from the demand for unambiguous, third-party analysis.
To tighten up the supply chain, buyers can ask for more than one certificate—sometimes an independent laboratory alongside the in-house report. Electronic documentation speeds things up and reduces human error in tracking test results. Audits become easier and faster, with the right paperwork at every stage. Across the industry, clear COA policies protect everyone, from lab technicians to patients at the pharmacy counter.
Every actor in the pharmaceutical world, from the factory floor up through the corporate office, understands that handling any pharma-grade chemical without a COA is a gamble. Adding Dibutyl Phthalate to your operation without proof of analysis stacks up risk, not value. Asking for documentation isn’t red tape—it’s basic self-protection, rooted in years of lessons learned from recalls and product failures. Certainty beats guesswork every time, which is why those sheets of analysis have become the invisible thread running through modern pharmaceutical trade.
| Names | |
| Preferred IUPAC name | bis(butyl) benzene-1,2-dicarboxylate |
| Other names |
DBP Dibutyl 1,2-benzenedicarboxylate Dibutyl ester of phthalic acid Phthalic acid dibutyl ester Dibutylphthalat Butyl phthalate |
| Pronunciation | /daɪˈbjuːtɪl ˈθæləˌbeɪt/ |
| Identifiers | |
| CAS Number | 84-74-2 |
| Beilstein Reference | 605297 |
| ChEBI | CHEBI:27787 |
| ChEMBL | CHEMBL1406 |
| ChemSpider | 8273 |
| DrugBank | DB02635 |
| ECHA InfoCard | 03-2119471838-36-0000 |
| EC Number | 201-557-4 |
| Gmelin Reference | 61213 |
| KEGG | C06428 |
| MeSH | Dibutyl Phthalate |
| PubChem CID | 3026 |
| RTECS number | TQ6125000 |
| UNII | 25O6CDD8ZQ |
| UN number | UN3082 |
| Properties | |
| Chemical formula | C16H22O4 |
| Molar mass | 278.34 g/mol |
| Appearance | Clear, colorless, oily liquid |
| Odor | Odorless |
| Density | 1.045 g/cm³ |
| Solubility in water | Insoluble in water |
| log P | 4.50 |
| Vapor pressure | 0.00013 mmHg (25°C) |
| Acidity (pKa) | 4.20 |
| Basicity (pKb) | pKb: 3.99 |
| Magnetic susceptibility (χ) | '−62.0 × 10⁻⁶ cm³/mol' |
| Refractive index (nD) | 1.490 to 1.493 |
| Viscosity | 12.40 cP |
| Dipole moment | 5.17 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 472.6 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -921.0 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -3297 kJ/mol |
| Pharmacology | |
| ATC code | G02CB02 |
| Hazards | |
| GHS labelling | GHS02, GHS07, GHS08, Warning, H226, H316, H319, H332, H360, P202, P210, P261, P280, P308+P313, P403+P233 |
| Pictograms | GHS02, GHS07, GHS08 |
| Signal word | Warning |
| Hazard statements | H360: May damage fertility or the unborn child. |
| Precautionary statements | P210, P233, P240, P241, P242, P243, P264, P273, P280, P302+P352, P305+P351+P338, P312, P337+P313, P362+P364 |
| NFPA 704 (fire diamond) | NFPA 704: 2-2-0 |
| Flash point | > 157°C |
| Autoignition temperature | 402°C |
| Explosive limits | Upper: 10.6% ; Lower: 0.5% |
| Lethal dose or concentration | LD50 oral rat 8000 mg/kg |
| LD50 (median dose) | LD50 (median dose) Oral - rat: 8000 mg/kg |
| NIOSH | NIOSH: PM1575000 |
| PEL (Permissible) | 5 mg/m³ |
| REL (Recommended) | 0.01 mg/kg bw |
| IDLH (Immediate danger) | NIOSH IDLH for Dibutyl Phthalate: 4000 mg/m3 |
| Related compounds | |
| Related compounds |
Dimethyl phthalate Diethyl phthalate Diisobutyl phthalate Benzyl butyl phthalate Di-n-octyl phthalate Di(2-ethylhexyl) phthalate (DEHP) |
Chengguan District, Lanzhou, Gansu, China
